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Department Affiliations | ||||||||||||||

Websites | ||||||||||||||

Rice Center for Quantum Materials | ||||||||||||||

Condensed Matter Physics @ Rice University | ||||||||||||||

Condensed Matter Seminars | ||||||||||||||

Keck Program in Quantum Materials | ||||||||||||||

Recent publications - search arxiv.org | ||||||||||||||

Research Areas | ||||||||||||||

Theoretical Condensed matter physics, specializing in strongly correlated electron systems: quantum criticality and emergent phases, iron-based high temperature superconductivity, topological metals driven by strong correlations. | ||||||||||||||

Research Interests 12-FEB-2018 | ||||||||||||||

Qimiao Si is the Harry C. and Olga K. Wiess Professor of Physics and Astronomy at Rice University. He came to the United States through the highly selective CUSPEA program in 1986, upon earning his B.S. in Physics from the University of Science and Technology of China. He received his Ph.D. in Physics in 1991 from the University of Chicago and subsequently did postdoctoral work at Rutgers University and University of Illinois at Urbana-Champaign. He has been on the faculty of Rice University since 1994 (making the actual move to Rice in 1995, after a year's leave of absence). He is particularly well known for his contributions to the theory of quantum criticality, which concerns the physics of matter undergoing a transition from one quantum state to another. He introduced and developed the theory of local quantum criticality, which involves the notion of critical destruction of Kondo entanglement. The theory goes beyond the Landau framework, and has received extensive support from experiments in magnetic heavy fermion systems. He has made seminal contributions to the young field of iron-based superconductors, contributing broadly to the understanding of electron correlations, quantum criticality, magnetism and superconductivity. In the area of topological states driven by strong correaltions, he has advanced a Weyl-Kondo semimetal state. He has introduced the Bose-Fermi Kondo model and the method of the extended dynamical mean field theory, and contributed to the early development of the dynamical mean field theory. Other topics he has studied include the spin dynamics of the high temperature cuprate superconductors, metal-insulator transition in disordered and interacting electrons in two dimensions, experimental signatures of spin-charge separation, non-Fermi liquid states in an extended Hubbard model and in quantum impurity systems, and Mott transition between metallic and correlated insulating phases of interacting electrons. Prof. Si was named a Sloan Research Fellow in 1996, and received a Cottrell Scholar Award from the Research Corporation for Science Advancement in 1998. He was elected a Fellow of the British Institute of Physics in 2004, the American Physical Society in 2005, and the American Association for the Advancement of Science in 2008. He received a Humboldt Prize from the Alexander von Humboldt Foundation in 2012. As of December 2017, he has published over 190 scientific articles (including 24 in Science, Nature, Nature Group Journals and PNAS, and 45 in Physical Review Letters) and has given more than 330 invited talks (including over 170 at conferences) on his research. He has served as a General Member of the Aspen Center for Physics (since 2009) and on the Advisory Editorial Board of Journal of Physics - Condensed Matter (2002-2006), and has co-chaired a number of international conferences and workshops, including the 2007 International Conference on Strongly Correlated Electron Systems (SCES'07), the 2014 KITP Program on Magnetism, Bad Metals and Superconductivity -- Iron Pnictides and Beyond, and the 2018 Aspen Winter Conference on High Temperature Superconductivity -- Unifying Themes in Diverse Materials. | ||||||||||||||

Research Interests 12-FEB-2018 | ||||||||||||||

Qimiao Si works in theoretical condensed matter physics, with an emphasis on quantum magnetism and superconductivity of strongly correlated electron systems. Strongly correlated electron systems are at the forefront of condensed matter physics. Their theoretical description is a challenge that provides rich opportunities for creative research. The fundamental question is how the electrons are organized, and, in particular, whether there are principles that are universal among the various classes of these strongly correlated materials. The overarching goal of the group's research is to seek such principles of universality. Along the way, it is also fascinating to explore the diversity of the phenomena that result from electron correlations. One area of Prof. Si's current interest is quantum criticality. He and his collaborators have advanced a by now well-known theory of local quantum criticality. Developed in the context of magnetic heavy fermion metals, which is a prototype system for quantum phase transitions, this theory features the "beyond-Landau" physics of critical Kondo destruction. A related topic of his recent research addresses novel phases that emerge in the vicinity of quantum critical points; for heavy fermion systems, his work here appears in the form of a proposed global phase diagram. He has also been interested in quantum critical physics in a variety of other contexts. Another focus of Prof. Si's current research concerns iron-based superconductors. One important aspect of the work is to address the bad-metal behavior in the normal state, which is attributed to a proximity to delocalization-localization transition. This line of consideration has opened up studies on orbital-selective Mott phenomena. A corollary of this approach is that magnetism is primarily driven by J1-J2 interactions, a notion that he and his collaborators have pioneered. This approach has led them to theoretically predict a magnetic quantum critical point in iso-electronically tuned iron pnictides, which has been verified by extensive recent experiments. His recent work has also explored the related magnetic frustration physics in the iron chalcogenides, including its effect on the nematicity in FeSe. Finally, the implications of such magnetic interactions for the unconventional superconductivity is being studied; recent work along this direction has shown how high Tc superconductivity may develop in the iron chalcogenides with seemingly unfavorable Fermi-surface conditions, and how orbital selectivity gives rise to a new superconducting pairing state. Another direction concerns topological metals driven by strong correlations. His group has recently advanced a class of Kondo-driven Weyl semimetal state. Recent experiments in heavy fermion semimetals have provided thermodynamic evidence for this Weyl-Kondo semimetal. A variety of other topics in correlated electron systems are of interest to the group. These range from non-Fermi liquid behavior, cuprate superconductors, quantum entanglement in many-body systems, disordered and interacting electronic systems, metal-insulator transitions, out of equilibrium behavior of electronic systems, spin transport, and the probe of spin-charge separation.
H.-H. Lai, S. E. Grefe, S. Paschen, and Q. Si, "Weyl-Kondo Semimetal in Heavy Fermion Systems", PNAS 115, 93 (2018). P. Goswami and Q. Si, "Dynamic zero modes of Dirac fermions and competing singlet phases of antiferromagnetic order", Phys. Rev. B95, 224438 (2017). K. Grube, S. Zaum, O. Stockert, Q. Si, H. v. Loehneysen, "Multidimensional entropy landscape of quantum criticality", Nature Phys. 13, 742 (2017). H.-H. Lai, W.-J. Hu, R. Yu, and Q. Si, "Antiferroquadrupolar order and rotational symmetry breaking in a generalized bilinear-biquadratic model on a square lattice", Phys. Rev. Lett. 118, 176401 (2017). E. M. Nica, R. Yu, and Q. Si, "Orbital-selective pairing and superconductivity in iron selenides", npj Quantum Materials 2, 24 (2017). Qi. Si, R. Yu and E. Abrahams, "High Temperature Superconductivity in Iron Pnictides and Chalcogenides", Nature Rev. Mater. 1, 16017 (2016). http://www.nature.com/articles/natrevmats201617. E. M. Nica, K. Ingersent, Qimiao Si, “Quantum criticality and global phase diagram of an Ising-anisotropic Kondo lattice”, arXiv:1603.03829. J. H. Pixley, R. Yu, and Qimiao Si, "Quantum phases of the Shastry-Sutherland Kondo lattice: implications for the global phase diagram of heavy fermion metals", Physical Review Letters 113, 176402 (2014). X. Lu, J. T. Park, R. Zhang, H. Luo, A. H. Nevidomskyy, Qimiao Si, and P. Dai, “Nematic spin correlations in the tetragonal state of uniaxial strained BaFe(2-x)Ni(x)As(2)”, Science 345, 657-660 (2014). R. Yu, P. Goswami, Q. Si, P. Nikolic, and J-X Zhu, "Superconductivity at the Border of Electron Localization and Itinerancy", Nature Communications 4, 2783 (2013); doi:10.1038/ncomms3783. R. Yu and Q. Si, "Orbital-selective Mott phase in multi-orbital models for alkaline selenides K(1-x)Fe(2-y)Se2", Physical Review Letters 110, 146402 (2013). P. Goswami and Q. Si, "Effects of Berry Phase and Instantons in One Dimensional Kondo-Heisenberg Model", Physical Review Letters 107, 126404 (2011). Q. Si and F. Steglich, "Heavy Fermions and Quantum Phase Transitions'', Science 329, 1161 (2010). Q. Si, "Quantum Criticality and Global Phase Diagram of Magnetic Heavy Fermions'', Phys. Status Solidi B247, 476 (2010). J. Dai, Q. Si, J.-X. Zhu, and E. Abrahams, "Iron Pnictides as a New Setting for Quantum Criticality", PNAS 106, 4118 (2009). Q. Si and E. Abrahams, "Strong Correlations and Magnetic Frustration in the High Tc Iron Pnictides", Physical Review Letters 101, 076401 (2008). P. Gegenwart, T. Westerkamp, C. Krellner, Y. Tokiwa, S. Paschen, C. Geibel, F. Steglich, E. Abrahams, and Q. Si, "Multiple energy scales at a quantum critical point", Science 315, 969-971 (2007) S. J. Yamamoto and Q. Si, "Fermi surface and antiferromagnetism in the Kondo lattice: an asymptotically exact solution in d>1 dimensions'', Physical Review Letters 99, 016401 (2007). S. Paschen, T. Luhmann, S. Wirth, P. Gegenwart, O. Trovarelli, C. Geibel, F. Steglich, P. Coleman, and Q. Si, "Hall-effect evolution across a heavy-fermion quantum critical point", Nature 432, 881-885 (2004). L. Zhu, M. Garst, A. Rosch and Q. Si, "Universally Diverging Grueneisen Parameter and the Magnetocaloric Effect close to Quantum Critical Points”, Physical Review Letters 91, 066404 (2003). Q. Si, S. Rabello, K. Ingersent and J. L. Smith, "Locally-critical Quantum Phase Transitions in Strongly Correlated Metals'', Nature 413, 804 (2001). | ||||||||||||||

Teaching Areas | ||||||||||||||

Physics | ||||||||||||||

Selected Publications | ||||||||||||||

Refereed articles | ||||||||||||||

B. A. Frandsen, K. M. Taddei, M. Yi, A. Frano, Z. Guguchia, R. Yu, Qimiao Si, D. E. Bugaris, R. Stadel, R. Osborn, S. Rosenkranz, O. Chmaissem, and R. J. Birgeneau "Local orthorhombicity in the magnetic C4 phase of the hole-doped iron-arsenide superconductor Sr(1-x)Na(x)Fe2As2." | ||||||||||||||

B. K. Rai, I. Oswald, W. Ban, C.-L. Huang, A. M. Hallas, M. N. Wilson, G. M. Luke, L. Harriger, Q. Huang, Y. Li, Sami Dzsaber, Julia Y. Chan, N. L. Wang, S. Paschen, J. Lynn, P. Dai, Q. Si, and E. Morosan "Low-carrier density and fragile magnetism in a Kondo lattice system." | ||||||||||||||

C.-C. Liu, P. Goswami, and Q. Si "Skyrmion defects and competing singlet orders in a half-filled antiferromagnetic Kondo-Heisenberg model on the honeycomb lattice." | ||||||||||||||

E. M. Nica, R. Yu, and Q. Si "Orbital-selective pairing and superconductivity in iron selenides." https://doi.org/10.1038/s41535-017-0027-6 | ||||||||||||||

H. Man, J. Guo, R. Zhang, R. U. Schonemann, Z.P. Yin, M. Fu, M. B. Stone, Q. Huang, Y. Song, W. Wang, D. Singh, F. Lochner, T. Hickel, I. Eremin, J. W. Lynn, C. Broholm, L. Balicas, Qimiao Si, Pengcheng Dai "Spin excitations and the Fermi surface of superconducting FeS." | ||||||||||||||

H.-H. Lai, W.-J. Hu, R. Yu, and Q. Si "Antiferroquadrupolar order and rotational symmetry breaking in a generalized bilinear-biquadratic model on a square lattice." | ||||||||||||||

J. Chen, Z. Wang, Y. Li, C. Feng, J. Dai, G. H. Cao, Z.-A. Xu, and Q. Si "Heavy fermion quantum criticality at dilute carrier limit in CeNi(2-delta)[As(1−x)$P(x))]2." | ||||||||||||||

J. Zhang, H. Zhao, M. Lv, S. Hu, Y. Isikawa, Y.-F. Yang, Qimiao Si, F. Steglich, and P. Sun "Kondo destruction in a quantum paramagnet with magnetic frustration." | ||||||||||||||

K. Grube, S. Zaum, O. Stockert, Q. Si, H. v. Loehneysen "Multidimensional entropy landscape of quantum criticality." | ||||||||||||||

M. Yi, A. Frano, D. H. Lu, Y. He, M. Wang, B. Frandsen, A. F. Kemper, R. Yu, Q. Si, L. Wang, M. He, F. Hardy, P. Schweiss, P. Adelmann, T. Wolf, M. Hashimoto, S.-K. Mo, Z. Hussain, M. Le Tacon, C. S. Nelson, A. E. Boehmer, D.-H. Lee, Z.-X. Shen, C. Meingast, and R. J. Birgeneau "Emergent Charge Order in Ba(1-x)Na(x)Fe2As2." | ||||||||||||||

Pallab Goswami and Qimiao Si "Dynamic zero modes of Dirac fermions and competing singlet phases of antiferromagnetic order." | ||||||||||||||

R. Yu and Q. Si "Orbital-selective Mott phase in multiorbital models for iron pnictides and chalcogenides." | ||||||||||||||

R. Yu, M. Yi, B. A. Frandsen, R. J. Birgeneau, and Qimiao Si "Emergent phases in iron pnictides: Double-Q antiferromagnetism, charge order and enhanced nematic correlations." | ||||||||||||||

S. Dzsaber, L. Prochaska, A. Sidorenko, G. Eguchi, R. Svagera, M. Waas, A. Prokofiev, Q. Si, and S. Paschen "Kondo Insulator to Semimetal Transformation Tuned by Spin-Orbit Coupling." | ||||||||||||||

S. Seiro, L. Jiao, S. Kirchner, S. Hartmann, S. Friedemann, C. Krellner, C. Geibel, Q. Si, F. Steglich, S. Wirth "Evolution of the Kondo lattice and non-Fermi liquid excitations in a heavy-fermion metal." | ||||||||||||||

S. Y. Jang, R. Kealhofer, C. John, S. Doyle, J.-S. Hong, J. H. Shim, Qimiao Si, O. Erten, J. D. Denlinger, James. G. Analytis "Direct visualization of coexisting channels of interaction in CeSb." | ||||||||||||||

V. Martelli, A. Cai, E. M. Nica, M. Taupin, A. Prokofiev, C. C. Liu, H.-H. Lai, R. Yu, R. Kuechler, A. M. Strydom, D. Geiger, J. Haenel, J. Larrea, Q. Si, and S. Paschen "Sequential localization and strange-metal behavior of a complex electron fluid." | ||||||||||||||

W.-J. Hu, S.-S. Gong, H.-H. Lai, Haoyu Hu, Qimiao Si, A. H. Nevidomskyy "Nematic Liquid Phase in a Frustrated Spin-1 Systems on the Square Lattice." | ||||||||||||||

Y. Zhou, Q. Wu, P. F. S. Rosa, R. Yu, J. Guo, W. Yi, S. Zhang, Z. Wang, H. Wang, S. Cai, K. Yang, A. Li, Z. Jiang, S. Zhang, X. Wei, Y. Huang, Y.-f. Yang, Z. Fisk, Qimiao Si, Z. X. Zhao, and Liling Sun "Quantum phase transition and destruction of Kondo effect in pressurized SmB6." https://doi.org/10.1016/j.scib.2017.10.008 | ||||||||||||||

Ang Cai, J. H. Pixley, Kevin Ingersent, and Qimiao Si, "Critical local moment fluctuations and enhanced pairing correlations in a cluster Anderson model", Phys. Rev. Lett., submitted; arXiv:1604.06449. | ||||||||||||||

E. M. Nica, K. Ingersent, and Qimiao Si, “Quantum criticality and global phase diagram of an Ising-anisotropic Kondo lattice”, Phys. Rev. Lett., submitted; arXiv:1603.03829. | ||||||||||||||

E. Schuberth, M. Tippmann, L. Steinke, S. Lausberg, A. Steppke, M. Brando, C. Krellner, C. Geibel, R. Yu, Qimiao Si, and F. Steglich, "Emergence of superconductivity in the canonical heavy-electron metal YbRh2Si2", Science http://dx.doi.org/10.1126/science.aaa9733 | ||||||||||||||

Felix Eilers, Kai Grube, Diego A. Zocco, Thomas Wolf, Michael Merz, Peter Schweiss, Rolf Heid, Robert Eder, Rong Yu, Jian-Xin Zhu, Qimiao Si, Takasada Shibauchi, and Hilbert v. Lohneysen, "Strain-driven approach to Quantum criticality in $A$Fe2As2 with $A$=K, Rb,and Cs", Phys. Rev. Lett. 116, 237003 (2016). | ||||||||||||||

G. M. Pang, M. Smidman, J. L. Zhang, L. Jiao, Z. F. Weng, E. M. Nica, Y. Chen, W. B. Jiang, Y. J. Zhang, H. S. Jeevan, P. Gegenwart, F. Steglich, Q. Si, and H. Q. Yuan, "Evidence for fully gapped d-wave superconductivity in CeCu2Si2", Phys. Rev. Lett., submitted; arXiv:1605.04786. | ||||||||||||||

J. Wu, Qimiao Si, and E. Abrahams, "Magnetic and Ising quantum phase transitions in a model for isoelectronically tuned iron pnictides", Phys. Rev. B http://link.aps.org/doi/10.1103/PhysRevB.93.104515 | ||||||||||||||

Jianda Wu, Wang Yang, Congjun Wu, Qimiao Si, "Quantum Critical Dynamics at Nonzero Temperatures in a Model for Insulating Magnets", Phys. Rev. X, submitted; arXiv:1605.07163. | ||||||||||||||

Qimiao Si, Rong Yu and Elihu Abrahams, "High Temperature Superconductivity in Iron Pnictides and Chalcogenides", Nature Rev. Mater. http://www.nature.com/articles/natrevmats201617 | ||||||||||||||

S. Paschen, S. Friedemann, S. Wirth, F. Steglich, S. Kirchner, and Q. Si, "Kondo Destruction in Heavy Fermion Quantum Criticality and the Photoemission Spectrum of YbRh2Si2", J. Magn. Magn. Mater. 400, 17-22 (2016). | ||||||||||||||

Wen-Jun Hu, Hsin-Hua Lai, Shou-Shu Gong, Rong Yu, Andriy H. Nevidomskyy, Qimiao Si, "Frustrated magnetism and quantum transitions of nematic phases in FeSe", Nat. Phys., submitted; arXiv:1606.01235. | ||||||||||||||

Xiao-Yong Feng, Hanting Zhong, Jianhui Dai and Qimiao Si, "Dirac-Kondo semimetals and topological Kondo insulators in the dilute carrier limit", PNAS, submitted; arXiv:1605.02380. | ||||||||||||||

Y. Song, Z. Yamani, C.-D. Cao, Y. Li, C.L. Zhang, J. Chen, Q. Z. Huang, H. Wu, J. Tao, Y. Zhu, W.Tian, S. X. Chi, H. Cao, Y.-B. Huang, M. Dantz, T. Schmitt, R. Yu, A. H. Nevidomskyy, E. Morosan, Qimiao Si, and Pengcheng Dai, "A Mott insulator continuously connected to iron pnictide superconductors", Nature Commun. 7, 13879 (2016). | ||||||||||||||

Yongkang Luo, Xin Lu, A. P. Dioguardi, P. F. S. Rosa, E. D. Bauer, Qimiao Si, J. D. Thompson, "Quantum criticality in CeRh(0.58)Ir(0.42)In5: Kondo-breakdown and spin-density critical points", Nature Commun., submitted; arXiv:1606.07848. | ||||||||||||||

Hsin-Hua Lai, Shou-Shu Gong, Wen-Jun Hu, and Qimiao Si, "Frustrated magnetism and bicollinear antiferromagnetic order in FeTe", Phys. Rev. X, submitted; arXiv:1608.08206. | ||||||||||||||

E. M. Nica, R. Yu, and Qimiao Si, "Glide reflection symmetry, Brillouin zone folding and superconducting pairing for the P4/nmm space group", Phys. Rev. B92, 174520 (2015). | ||||||||||||||

H. Man, X. Lu, J. S. Chen, R. Zhang, W. Zhang, H. Luo, J. Kulda, A. Ivanov, T. Keller, E. Morosan, Qimiao Si, and P. Dai, "Electronic nematic correlations in the stress free tetragonal state of BaFe(2-x)Ni(x)As2", Phys. Rev. B92, 134521 (2015). | ||||||||||||||

J. H. Pixley, Ang Cai, and Qimiao Si, “Cluster Extended Dynamical Mean Field Approach and Unconventional Superconductivity”, Phys. Rev. B91, 125127 (2015). | ||||||||||||||

J. H. Pixley, Lili Deng, Kevin Ingersent, and Qimiao Si, “Pairing Correlations Near a Kondo-Destruction Quantum Critical Point”, Phys. Rev. B91, Rapid Commun., 201109(R) (2015). | ||||||||||||||

J. H. Pixley, R. Yu, S. Paschen, and Qimiao Si, "Global Phase Diagram and Momentum Distribution of Single-Particle Excitations in Kondo insulators", Phys. Rev. Lett., submitted; arXiv:1509.02907. | ||||||||||||||

L. Jiao, Y. Chen, Y. Kohama, D. Graf, E. D. Bauer, J. Singleton, J.-X. Zhu, Z. F. Weng, G. M. Pang, T. Shang, J. L. Zhang, H. O. Lee, T. Park, M. Jaime, J. D. Thompson, F. Steglich, and Q. Si, and H. Q. Yuan, “Fermi-surface reconstruction and multiple quantum phase transitions in the antiferromagnet CeRhIn5”, PNAS 112, 673-678 (2015). | ||||||||||||||

M. Yi, Z.-K. Liu, Y. Zhang, R. Yu, J.-X. Zhu, J. J. Lee, R. G. Moore, F. T. Schmitt, W. Li, S. C. Riggs, J.-H. Chu, B. Lv, J. Hu, T. J. Liu, M. Hashimoto, S.-K. Mo, Z. Hussain, Z. Q. Mao, C. W. Chu, I. R. Fisher, Q. Si, Z.-X. Shen, and D. H. Lu, "Observation of universal strong orbital-dependent correlation effects in iron chalcogenides", Nature Commun. 6, 7777 (2015). | ||||||||||||||

Rong Yu and Qimiao Si, “Antiferroquadrupolar and Ising-nematic orders of a frustrated bilinear-biquadratic Heisenberg model and implications for the magnetism of FeSe”, Phys. Rev. Lett. 115, 116401 (2015). | ||||||||||||||

W. Ding, S. Paschen, and Qimiao Si, "Anomalous Hall effect and quantum criticality in geometrically frustrated heavy fermion metals", Phys. Rev. Lett., submitted; arXiv:1507.07328. | ||||||||||||||

Y. Song, X. Lu,, D. L. Abernathy, D. W. Tam, J. L. Niedziela, W. Tian, H. Luo, Qimiao Si, and P. Dai, "Energy dependence of the spin excitation anisotropy in uniaxial-strained BaFe(1.9)Ni(0.1)As2", Phys. Rev. B92, 180504(R) (2015). | ||||||||||||||

Z. K. Liu, M. Yi, Y. Zhang, J. Hu, R. Yu, J. -X. Zhu, R. -H. He, Y. L. Chen, M. Hashimoto, R. G. Moore, S. -K. Mo, Z. Hussain, Q. Si, Z. Q. Mao, D. H. Lu, Z. X. Shen, "Experimental Observation of Incoherent-Coherent Crossover and Orbital Dependent Band Renormalization in Iron Chalcogenide Superconductors", Phys. Rev. B92, 235138 (2015). | ||||||||||||||

Zhang, C., J. T. Park, Xingye Lu, Rong Yu, Yu Li, Wenliang Zhang, Yang Zhao,J. W. Lynn, Qimiao Si, and Pengcheng Dai, “Neutron spin resonance as a probe of superconducting gap anisotropy in partially detwinned electron underdoped NaFe(0.985)Co(0.015)As”, Phys. Rev. B 91, 104520 (2015). | ||||||||||||||

C. Zhang, Y. Su, L.-P. Regnault, Y. Su, M. Enderle, J. Julda, G. Tan, Z. C. Sims, T. Egami, Qimiao Si, and P. Dai, "Anisotropic neutron spin resonance in underdoped superconducting NaFe(1-x)Co(x)As", Phys. Rev. B90, 140502(R) (2014). | ||||||||||||||

F. Steglich, H. Pfau, S. Lausberg, P. Sun, U. Stockert, M. Brando, S. Friedemann, C. Krellner, C. Geibel, S. Wirth, S. Kirchner, E. Abrahams, and Qimiao Si, "Evidence for a Kondo destroying quantum critical point in YbRh2Si2", J. Phys. Soc. Jpn. 83, 061001 (2014). http://dx.doi.org/10.7566/JPSJ.83.061001 | ||||||||||||||

J. H. Pixley, Rong Yu, and Qimiao Si, "Quantum phases of the Shastry-Sutherland Kondo lattice: implications for the global phase diagram of heavy fermion metals", Phys. Rev. Lett. 113, 176402 (2014) http://dx.doi.org/10.1103/PhysRevLett.113.176402 | ||||||||||||||

J. Wu, M. Kormos and Qimiao Si, "Finite temperature spin dynamics in a perturbed quantum critical Ising chain with an E8 symmetry", Phys. Rev. Lett. 113, 247201 (2014). http://dx.doi.org/10.1103/PhysRevLett.113.247201 | ||||||||||||||

P. Gao, R. Yu, L. Sun, H. Wang, Z. Wang, Q. Wu, M. Fang, G. Chen, J. Guo, C. Zhang, D. Gu, H. Tian, J. Li, J. Liu, Y. Li, X. Li, Qimiao Si, and Z. Zhao, "Role of the 245 phase in alkaline iron selenide superconductors revealed by high-pressure studies", Phys. Rev. B89, 094514 (2014). | ||||||||||||||

Pallab Goswami and Qimiao Si, "Topological defects of Neel order and Kondo singlet formation for Kondo-Heisenberg model on a honeycomb lattice", Phys. Rev. B89, 045124 (2014). | ||||||||||||||

Qimiao Si, J. H. Pixley, Emilian Nica, Seiji J. Yamamoto, P. Goswami, R. Yu, and S. Kirchner, "Kondo Destruction and Quantum Criticality in Kondo Lattice Systems", J. Phys. Soc. Jpn. 83, 061005 (2014). http://dx.doi.org/10.7566/JPSJ.83.061005 | ||||||||||||||

Rong Yu, Jian-Xin Zhu and Qimiao Si, "Orbital-selective superconductivity, gap anisotropy and spin resonance excitations in a multiorbital t-J1-J2 model for iron pnictides", Phys. Rev. B 89, 024509 (2014). | ||||||||||||||

W. Ding, R. Yu, Qimiao Si, and E. Abrahams, "Effective Exchange Interactions for Bad Metals and Implications for Iron-based Superconductors", Phys. Rev. Lett., submitted (2014); arXiv:1410.8118. | ||||||||||||||

X. Lu, J. T. Park, R. Zhang, H. Luo, A. H. Nevidomskyy, Qimiao Si, and P. Dai, "Nematic spin correlations in the tetragonal state of uniaxial strained BaFe(2-x)Ni(x)As2", Science 345, 657-660 (2014). http://dx.doi.org/10.1126/science.1251853 | ||||||||||||||

Y. Luo, L. Pourovskii, S. Rowley, Y. Li, C. Feng, A. Georges, J. Dai, G. H. Cao, Z. A. Xu, Qimiao Si, and N. P. Ong, "Heavy Fermion Quantum Criticality and Destruction of the Kondo Effect in a Nickel Oxypnictide'', Nature Materials 13, 777-781 (2014). http://dx.doi.org/10.1038/nmat3991 | ||||||||||||||

C. Zhang, Rong Yu, Y. Su, Y. Song, M. Wang, G. Tan, T. Egami, J. A. Fernandez-Baca, E. Faulhaber, Qimiao Si, and P. Dai, "Double spin resonances and gap anisotropy in superconducting Co-underdoped NaFeAs", Phys. Rev. Lett. 111, 207002 (2013). | ||||||||||||||

D. D. Khalyavin, D. T. Adroja, P. Manuel, A. Daoud-Aladine, M. Kosaka, K. Kondo, K. A. McEwen, J. H. Pixley, and Qimiao Si, "Field-induced long-range magnetic order in the spin-singlet ground state system YbAl3C3: Neutron diffraction study", Phys. Rev. B 87, Rapid Commun., 220406(R) (2013). | ||||||||||||||

Emilian M. Nica, Kevin Ingersent, Jian-Xin Zhu, and Qimiao Si, "Quantum critical Kondo destruction in the Bose-Fermi Kondo model with a local transverse field", Phys. Rev. B 88, 014414 (2013) | ||||||||||||||

J. H. Pixley, Stefan Kirchner, Kevin Ingersent, and Qimiao Si, "Quantum criticality in the pseudo-gap Bose-Fermi Anderson and Kondo models: Interplay between fermion- and boson-induced Kondo destruction", Phys. Rev. B 88, 245111 (2013). | ||||||||||||||

M. Yi, D. H. Lu, R. Yu, S. Riggs, J.-H. Chu, B. Lv, Z. Liu, M. Lu, Y. Cui, M. Hashimoto, S.-K. Mo, Z. Hussain, C. W. Chu, I. R. Fisher, Q. Si, and Z.-X. Shen, "Observation of temperature-induced Crossover to an orbital-selective Mott phase in A(x)Fe(2-y)Se2 (A=K, Rb) superconductors", Phys. Rev. Lett. 110, 067003 (2013). | ||||||||||||||

P. Ribeiro, Qimiao Si, and S. Kirchner, "Local quantum criticality out of equilibrium -- effective temperature and scaling in the steady state regime", Europhys. Lett. (EPL) 102, 50001 (2013). | ||||||||||||||

Qimiao Si, "Condensed Matter Physics -- Hidden is More", Nature 493, N&V, 619-620 (2013) http://dx.doi.org/10.1038/493619a | ||||||||||||||

Qimiao Si and Silke Paschen, "Quantum phase transitions in heavy fermion metals and Kondo insulators", Phys. Status Solidi B 250, 425-438 (2013). http://dx.doi.org/10.1002/pssb.201300005 | ||||||||||||||

Rong Yu and Qimiao Si, "Orbital-selective Mott Phase in Multiorbital Models for Alkaline Iron Selenides K(1-x)Fe(2-y)Se2", Phys. Rev. Lett. 110, 146402 (2013). | ||||||||||||||

Rong Yu, Jian-Xin Zhu and Qimiao Si, "Orbital-dependent effects of electron correlations in microscopic models for iron-based superconductors", Current Opinion in Solid State and Materials Science 17, 65-71 (2013) http://dx.doi.org/10.1016/j.cossms.2013.05.003 | ||||||||||||||

Rong Yu, Pallab Goswami, Qimiao Si, Predrag Nikolic, and Jian-Xin Zhu, "Superconductivity at the Border of Electron Localization and Itinerancy", Nature Communications 4, 2783 (2013) http://dx.doi.org/10.1038/ncomms3783 | ||||||||||||||

S. Friedemann, S. Paschen, C. Geibel, S. Wirth, F. Steglich, S. Kirchner, E. Abrahams, and Q. Si, "Comment on `Zeeman-driven Lifshitz transition: A model for the experimentally observed Fermi-surface reconstruction in YbRh2Si2' ", Phys. Rev. Lett. 111, 139701 (2013) | ||||||||||||||

X. Lu, H. Gretarsson, R. Zhang, X. Liu, H. Luo, W. Tian, M. Laver, Z. Yamani, Y.-J. Kim, A. H. Nevidomskyy, Qimiao Si, P. Dai, "Avoided quantum criticality and magnetoelastic coupling in BaFe(2-x)Ni(x)As2", Phys. Rev. Lett. 110, 257001 (2013). | ||||||||||||||

X.-Y. Feng, J. Dai, C.-H. Chung, and Qimiao Si, "Competing topological and Kondo insulator phases on a honeycomb lattice", Phys. Rev. Lett. 111, 016402 (2013). | ||||||||||||||

E. Morosan, D. Natelson, Andriy H. Nevidomskyy, and Qimiao Si, "Strongly correlated materials", Advanced Materials 24, 4896-4923 (2012). | ||||||||||||||

H. Pfau, S. Hartmann, U. Stockert, P. Sun, S. Lausberg, M. Brando, S. Friedemann, C. Krellner, C. Geibel, S. Wirth, S. Kirchner, E. Abrahams, Qimiao Si, F. Steglich, "Thermal and Electrical Transport across a Magnetic Quantum Critical Point", Nature 484, 493-497 (2012); doi: 10.1038/nature11072. | ||||||||||||||

J. Custers, K.-A. Lorenzer, M. Mueller, A. Prokofiev, A. Sidorenko, H. Winkler, A. M. Strydom, Y. Shimura, T. Sakakibara, R. Yu, Q. Si, and S. Paschen, "Destruction of Kondo effect in cubic heavy fermion compound Ce3Pd20Si6", Nature Materials 11, 189-194 (2012); doi:10.1038/nmat3214. | ||||||||||||||

J.H. Pixley, S. Kirchner, K. Ingersent and Qimiao Si, "Kondo destruction and valence fluctuations in an Anderson model", Phys. Rev. Lett. 109, 086403 (2012). | ||||||||||||||

Oliver Stockert, Stefan Kirchner, Frank Steglich, and Qimiao Si, "Superconductivity in Ce- and U-based `122' heavy-fermion compounds", J. Phys. Soc. Jpn. 81, 011001 (2012); DOI: 10.1143/JPSJ.81.011001. | ||||||||||||||

Rong Yu and Qimiao Si, "U(1) Slave-spin theory and its application to Mott transition in a multi-orbital model for iron pnictides", Phys. Rev. B86, 085104 (2012). | ||||||||||||||

Rong Yu, Zhentao Wang, Pallab Goswami, Andriy Nevidomskyy, Qimiao Si, and Elihu Abrahams, "Spin Dynamics of a J1-J2-K Model for the Paramagnetic Phase of Iron Pnictides", Phys. Rev. B86, 085148 (2012). | ||||||||||||||

S. Nair, S. Wirth, S. Friedemann, F. Steglich, Q. Si and A. J. Schofield, "Hall effect in heavy-fermion metals", Adv. Phys. 61, 583-664 (2012); http://dx.doi.org/10.1080/00018732.2012.730223. | ||||||||||||||

Stefan Kirchner, Kevin Ingersent, and Qimiao Si, "Quantum criticality of the sub-ohmic spin-boson model", Phys. Rev. B85, 075113 (2012); doi: 10.1103/PhysRevB.85.075113. | ||||||||||||||

Elihu Abrahams and Qimiao Si, "Quantum criticality in the iron pnictides and chalcogenides", J. Phys.: Condens. Matter 23, 223201 (2011). | ||||||||||||||

Jian-Xin Zhu, Rong Yu, A. V. Balatsky, and Qimiao Si, "Local Electronic Structure around a Single Impurity as a Test of Pairing Symmetry in (K,Tl)_yFe_xSe2 Superconductors", Phys. Rev. Lett. 107, 167002 (2011). | ||||||||||||||

M. T. Glossop, S. Kirchner, J. H. Pixley, and Qimiao Si, "Critical Kondo destruction in a pseudogap Anderson model: scaling and relaxational dynamics",Phys. Rev. Lett. 107, 076404 (2011) | ||||||||||||||

O. Stockert, J. Arndt, E. Faulhaber, C. Geibel, H. S. Jeevan, S. Kirchner, M. Loewenhaupt, K. Schmalzl, W. Schmidt, Qimiao Si, F. Steglich, "Magnetically driven superconductivity in CeCu2Si2", Nature Physics 7, 119-124 (2011). | ||||||||||||||

Pallab Goswami and Qimiao Si, "Effects of Berry phase and instantons in one dimensional Kondo-Heisenberg model", Phys. Rev. Lett. 107, 126404 (2011). | ||||||||||||||

Pallab Goswami, Rong Yu, Qimiao Si, and Elihu Abrahams, "Spin Dynamics of a J1-J2 Antiferromagnet and its Implications for Iron Pnictides", Phys. Rev. B84, 155108 (2011). | ||||||||||||||

Rong Yu and Qimiao Si, "Mott Transition in Multi-Orbital Models for Iron Pnictides", Phys. Rev. B84, 235115 (2011). | ||||||||||||||

Rong Yu, Jian-Xin Zhu, Qimiao Si, "Mott transition in Modulated Lattices and Parent Insulator of (K,Tl)_yFe_xSe2 Superconductors", Phys. Rev. Lett. 106, 186401 (2011). | ||||||||||||||

Rong Yu, Pallab Goswami, and Qimiao Si, "The magnetic phase diagram of an extended J1-J2 model on a modulated square lattice and its implications for the antiferromagnetic phase of K_yFe_xSe2", Phys. Rev. B84, 094451 (2011). | ||||||||||||||

S. Friedemann, N. Oeschler, S. Wirth, C. Krellner, C. Geibel, F. Steglich, S. Paschen, S. Kirchner, and Qimiao Si, "Discontinuous Hall coefficient at the quantum critical point in YbRh2Si2", J. Phys.: Condens. Matter 23, 094216 (2011). | ||||||||||||||

S. Friedemann, S. Wirth, S. Kirchner, Q. Si, S. Hartmann, C. Krellner, C. Geibel, T. Westerkamp, M. Brando, and F. Steglich, "Break up of heavy fermions at an antiferromagnetic instability", J. Phys. Soc. Jpn. 80, SA002 (2011). | ||||||||||||||

C. de la Cruz, W. Z. Hu, S. Li, Q. Huang, J. W. Lynn, M. A. Green, G. F. Chen, N. L. Wang, H. A. Mook, Qimiao Si, Pengcheng Dai, "Lattice distortion and magnetic quantum phase transitions in CeFeAs(1-x)PxO", Phys. Rev. Lett. 104, 017204 (2010). | ||||||||||||||

J.-X. Zhu, R. Yu, H. Wang, L. L. Zhao, M. D. Jones, J. Dai, E. Abrahams, E. Morosan, M. Fang, and Qimiao Si,"Band Narrowing and Mott Localization in Iron Oxychalcogenides La2O2Fe2O(Se,S)2'', Phys. Rev. Lett. 104, 216405 (2010). | ||||||||||||||

Nabil Iqbal, Hong Liu, Mark Mezei, and Qimiao Si, "Quantum phase transitions in holographic models of magnetism and superconductors", Phys. Rev. D82, 045002 (2010). | ||||||||||||||

Pallab Goswami, Predrag Nikolic, and Qimiao Si, "Superconductivity in Multi-orbital t-J1-J2 Model and its Implications for Iron Pnictides", EPL 91, 37006 (2010). | ||||||||||||||

Qimiao Si, "Quantum Criticality and Global Phase Diagram of Magnetic Heavy Fermions", Physica Status Solidi B247, 476-484 (2010); http://arxiv.org/abs/arXiv:0912.0040. | ||||||||||||||

Qimiao Si and Frank Steglich, "Heavy Fermions and Quantum Phase Transitions", Science 329, 1161-1166 (2010). | ||||||||||||||

S. Friedemann, N. Oeschler, S. Wirth, C. Krellner, C. Geibel, F. Steglich, S. Paschen, S. Kirchner, and Qimiao Si, "Fermi-surface collapse and quantum-dynamical scaling near a quantum critical point", PNAS 107, 14547-14551 (2010). | ||||||||||||||

S. Kirchner and Qimiao Si, "On the concept of effective temperature in current carrying quantum critical states", Phys. Status Solidi B247, 631-634 (2010).; http://arXiv.org/abs/0909.3925 | ||||||||||||||

Seiji J. Yamamoto and Qimiao Si, "Global Phase Diagram of the Kondo Lattice: From Heavy Fermion Metals to Kondo Insulators", J. Low Temp. Phys. 161, 233-262 (2010). | ||||||||||||||

Seiji J. Yamamoto and Qimiao Si, "Metallic Ferromagnetism in the Kondo Lattice'', PNAS 107, 15704-15707 (2010).
| ||||||||||||||

Seiji Yamamoto and Qimiao Si, "Renormalization Group for Mixed Fermion-Boson Systems", Phys. Rev. B81, 205106 (2010). | ||||||||||||||

Jianhui Dai, Jian-Xin Zhu, and Qimiao Si, "The f-spin physics of rare-earth iron pnictides: influence of d-electron antiferromagnetic order on heavy fermion phase diagram", Phys. Rev. B 80, 020505(R) (2009). | ||||||||||||||

Jianhui Dai, Qimiao Si, Jian-Xin Zhu, and Elihu Abrahams, "Iron pnictides as a new setting for quantum criticality", PNAS 106, 4118-4121 (2009) | ||||||||||||||

Qimiao Si, "Iron pnictide superconductors: Electrons on the verge", Nature Physics 5, 629-630 (2009). | ||||||||||||||

Qimiao Si, Elihu Abrahams, Jianhui Dai, and Jian-Xin Zhu, "Correlation effects in the iron pnictides", New Journal of Physics 11, 045001 (2009). | ||||||||||||||

Stefan Kirchner and Qimiao Si, "Critical Kondo destruction and the violation of the quantum-to-classical mapping of quantum criticality", Physica B 404, 2904-2907 (2009). | ||||||||||||||

Stefan Kirchner and Qimiao Si, "Quantum Criticality out of Equilibrium: Steady State in a Magnetic Single-Electron Transistor", Phys. Rev. Lett. 103, 206401 (2009). | ||||||||||||||

Stefan Kirchner, Qimiao Si, and Kevin Ingersent, "Finite Size Scaling of Classical Long-Ranged Ising Chains and the Criticality of Dissipative Quantum Impurity Models", Phys. Rev. Lett. 102, 166405 (2009). | ||||||||||||||

Jianhui Dai, C. J. Bolech, Qimiao Si, "The Bose-Fermi Kondo Model in an Exactly Solvable Limit." | ||||||||||||||

Philipp Gegenwart, Qimiao Si, and Frank Steglich "Quantum Criticality in Heavy Fermion Metals." | ||||||||||||||

Qimiao Si, Elihu Abrahams "Strong Correlations and Magnetic Frustration in the High Tc Iron Pnictides." | ||||||||||||||

Seiji J Yamamoto, Qimiao Si, "Fermi Surface and Magnetism in the Kondo lattice: a Continuum Field Theory Approach." | ||||||||||||||

Stefan Kirchner, Qimiao Si "Berry Phase and the Breakdown of the Quantum to Classical Mapping for the Quantum Critical Point of the Bose-Fermi Kondo model." | ||||||||||||||

Stefan Kirchner, Qimiao Si "Bose-Fermi Kondo Model with Ising Anisotropy: Cluster-Monte Carlo Approach." | ||||||||||||||

Stefan Kirchner, Qimiao Si "Magnetic Single-Electron Transistor as a Tunable Model System for Kondo-Destroying Quantum Criticality." | ||||||||||||||

Stefan Kirchner, Qimiao Si, "Scaling and Enhanced Symmetry at the Quantum Critical Point of the Sub-Ohmic Bose-Fermi Kondo Model." | ||||||||||||||

J.-X. Zhu, S. Kirchner, R. Bulla, and Qimiao Si, "Zero-Temperature Magnetic Transition in an Easy-Axis Kondo Lattice Model." | ||||||||||||||

Jianhui Dai, Qimiao Si, and C. J. Bolech, "The Bose-Fermi Kondo Model with a Singular Dissipative Spectrum: Exact Solutions and their Implications." | ||||||||||||||

P. Gegenwart, T. Westerkamp, C. Krellner, Y. Tokiwa, S. Paschen, C. Geibel, F. Steglich, E. Abrahams, and Qimiao Si, "Multiple energy scales at a quantum critical point." | ||||||||||||||

Seiji J. Yamamoto and Qimiao Si, "Fermi surface and antiferromagnetism in the Kondo lattice: an asymptotically exact solution in d>1 dimensions." | ||||||||||||||

Jian-Xin Zhu, A. V. Balatsky, T. P. Devereaux, Qimiao Si, J. Lee, K. McElroy, and J. C. Davis, "Fourier-Transformed Local Density of States and Tunneling into a d-Wave Superconductor with Bosonic Modes." | ||||||||||||||

Jian-Xin Zhu, K. McElroy, J. Lee, T. P. Devereaux, Qimiao Si, J. C. Davis, and A. V. Balatsky, "Effects of Pairing Potential Scattering on Fourier-Transformed Inelastic Tunneling Spectra in High-$T_c$ Cuprate Superconductors with Bosonic Modes." | ||||||||||||||

Qimiao Si, "Global Magnetic Phase Diagram and Local Quantum Criticality in Heavy Fermion Metals." | ||||||||||||||

S. D. Wilson, S. Li, P. Dai, W. Bao, J-H Chung, H. J. Kang, S-H Lee, S. Komiya, Y. Ando, and Qimiao Si, "Evolution of low-energy spin dynamics in the electron-doped high-transition-temperature superconductor Pr$_{0.88}$LaCe$_{0.12}$CuO$_{4-\delta}$." | ||||||||||||||

Qimiao Si, Jian-Xin Zhu, and D. R. Grempel "Magnetic Quantum Phase Transitions in Kondo Lattices." | ||||||||||||||

S. Kirchner, L. Zhu, Q. Si, and D. Natelson "Quantum Criticality in Ferromagnetic Single-Electron Transistors." | ||||||||||||||

S. Kirchner, L. Zhu, and Q. Si "Destruction of the Kondo effect in a multi-channel Bose-Fermi Kondo model." | ||||||||||||||

Eugene Pivovarov and Q. Si "Transitions from small to large Fermi momenta in a one-dimensional Kondo lattice model." | ||||||||||||||

J. Sun, O. Rambow, and Q. Si "Orthogonality Catastrophe in Bose-Einstein Condensates." | ||||||||||||||

J.-X. Zhu, J. Sun, Q. Si, and A. V. Balatsky "Effects of a Collective Spin Resonance Mode on the STM Spectra of D-Wave Superconductors." | ||||||||||||||

Lijun Zhu, Stefan Kirchner, Qimiao Si, and Antoine Georges "Quantum critical properties of the Bose-Fermi Kondo Model in a large-N limit." | ||||||||||||||

S. A. Grigera, A. J. Schofield, S. Rabello, and Q. Si "Momentum resolved tunneling in a Luttinger Liquid." | ||||||||||||||

S. Paschen, T. Luhmann, S. Wirth, P. Gegenwart, O. Trovarelli, C. Geibel, F. Steglich, P. Coleman, and Q. Si "Hall-effect evolution across a heavy-fermion quantum critical point." | ||||||||||||||

Ya. B. Bazaliy, R. Ramazashvili, Q. Si, and M. R. Norman "Magnetotransport near a quantum critical point in a simple metal." | ||||||||||||||

Book chapters | ||||||||||||||

Q. Si, "Quantum Criticality and the Kondo Lattice'', Chapter in "Understanding Quantum Phase Transitions'', ed. L. D. Carr (Taylor & Francis, Boca Rato, 2011). | ||||||||||||||

Refereed conference papers | ||||||||||||||

F. Steglich, O. Stockert, S. Wirth, C. Geibel, H. Q. Yuan, S. Kirchner, and Q. Si, "Routes to heavy-fermion superconductivity" J. Phys. Conf. Series 449, 012028 (2013). http://dx.doi.org/10.1088/1742-6596/449/1/012028 | ||||||||||||||

Rong Yu, Qimiao Si, Pallab Goswami, and Elihu Abrahams, "Electron Correlation and Spin Dynamics in Iron Pnictides and Chalcogenides", J. Phys.: Conf. Ser. 449, 012025 (2013) http://dx.doi.org/10.1088/1742-6596/449/1/012025 | ||||||||||||||

F. Steglich, J. Arndt, O. Stockert, S. Friedemann, M. Brando, C. Klingner, C. Krellner, C. Geibel, S. Wirth, S. Kirchner and Q. Si, "Magnetism, f-electron localization and superconductivity in 122-type heavy-fermion metals", J. Phys.: Condens. Matter 24, 294201 (2012). | ||||||||||||||

J. H. Pixley, Stefan Kirchner, M. T. Glossop and Qimiao Si, "Continuous-Time Monte Carlo study of the pseudogap Bose-Fermi Kondo model", J. Phys.: Conf. Ser. 273, 012019 (2011). | ||||||||||||||

Jianda Wu, Lijun Zhu, Qimiao Si, "Entropy accumulation near quantum critical points: effects beyond hyperscaling", J. Phys.: Conf. Ser. 273, 012019 (2011). | ||||||||||||||

Conference papers | ||||||||||||||

Q. Si "Quantum Critical Metals: beyond the Order Parameter Fluctuations." | ||||||||||||||

Presentations | ||||||||||||||

Invited Talks | ||||||||||||||

" Correlated Electrons in Iron Based Superconductors: Quantum Criticality and Emergent Phases ." Theoretical and Experimental Magnetism Meeting, Abingdon, UK. (July 5-6, 2017) | ||||||||||||||

" Correlated electrons and iron-based superconductivity ." Emergence in disordered, interacting and living systems: Abrahams@90, Aspen, CO. (Aug. 12, 2017) | ||||||||||||||

" Effects of Berry phase and topological defects in antiferromagnetic quantum phase transitions ." Workshop on Path Integration in Complex Dynamical Systems, Lorentz Center, Leiden, the Netherlands. (Feb. 6-10, 2017) | ||||||||||||||

" Electron correlations and orbital selectivity in iron-based superconductors ." Zhejiang Workshop on Correlated Matter, Hangzhou, China. (Oct 10-13, 2017) | ||||||||||||||

" Frustrated Magnetism and Superconductivity in Iron Chalcogenides ." Workshop on Common Threads in the Electronic Phase Diagram of Unconventional Superconductors, Lorentz Center, Leiden, the Netherlands. (Feb. 27-March 3, 2017) | ||||||||||||||

" Global phase diagram in antiferromagnetic and multipolar heavy fermion systems ." International Conference on Strongly Correlated Electron SCES-2017, Prague, Czech Republic. (July 17-21, 2017) | ||||||||||||||

" Orbital-selective effects and iron-based superconductivity ." Conference on Multicomponent and Strongly Correlated Superconductivity, Stockholm, Sweden. (Aug 17-21, 2017) | ||||||||||||||

" Quantum Criticality and Emergent Phases in Correlated Electron Systems ." International Conference on Quantum Criticality and Novel Phases (QCNP2017), Berlin, Germany. (Feb 27--March 1, 2017) | ||||||||||||||

" Quantum Criticality and Emergent Phases in Correlated Systems ." Condensed Matter Seminar, University of California at Berkeley, Berkeley, CA. (Jan. 30, 2017) | ||||||||||||||

" Quantum Criticality and Emergent Phases in Correlated Systems ." Condensed Matter Seminar, Caltech, Pasadena, CA. (May 8, 2017) | ||||||||||||||

" Quantum Criticality and Emergent Phases in Correlated Systems ." Condensed Matter Seminar, University of Washington at Seattle, Seattle, Washington. (May 25, 2017) | ||||||||||||||

" Quantum Criticality and Emergent Phases in Correlated Systems ." Condensed Matter Seminar, University of California at San Diego, San Diego, CA. (May 17, 2017) | ||||||||||||||

" Strong Correlations and Spin-Orbit Couplings in Kondo Lattice Systems ." Workshop on Strongly Correlated Materials: Topology and Quantum Phase Transitions, Rice University, Houston. (Jan. 23, 2017) | ||||||||||||||

" Weyl-Kondo Semimetal in Heavy Fermion Systems ." Special symposium talk, Zhejiang Workshop on Correlated Matter, Hangzhou, China. (Oct 10-13, 2017) | ||||||||||||||

"Correlated Electrons in Iron Based Superconductors: Magnetism and Nematicity in FeSe", Theoretical and Experimental Magnetism Meeting, Rutherford Appleton Laboratory, UK, June 16-17, 2016. | ||||||||||||||

"Frustrated Magnetism and Superconductivity in Iron Pnictides and Chalcogenides", Condensed Matter Seminar, Princeton University, April 18, 2016. | ||||||||||||||

"Frustrated Magnetism and Superconductivity in Iron Pnictides and Chalcogenides", NORDITA Workshop on Multi-Component and Strongly-Correlated Superconductors, Stockholm, Sweden, July 3 -10, 2016. | ||||||||||||||

"Frustrated Magnetism and Superconductivity in Iron Pnictides and Chalcogenides", CMTC Seminar, University of Maryland, April 19, 2016. | ||||||||||||||

"Frustrated Magnetism and Superconductivity in Iron Pnictides and Chalcogenides", APS March Meeting, Baltimore, MD, March 14-18, 2016. | ||||||||||||||

"Frustrated Magnetism and Superconductivity in Iron Pnictides and Chalcogenides", Goethe-University Frankfurt, June 28, 2016. | ||||||||||||||

"Frustrated Magnetism and Superconductivity in Iron Pnictides and Chalcogenides", Invited presentation, EPiQS Workshop on Intertwined Orders in Strongly Correlated Systems, Laguna Beach, CA, Jan 29-31, 2016. | ||||||||||||||

"Frustrated Magnetism and Superconductivity in Iron Pnictides and Chalcogenides", University of Augsburg, Augsburg, Germany, June 7, 2016. | ||||||||||||||

"Frustrated Magnetism and Superconductivity in Iron Pnictides and Chalcogenides", Condensed Matter Seminar, University of California at Davis, Oct. 25, 2016. | ||||||||||||||

"Frustrated Magnetism and Superconductivity in Iron Pnictides and Chalcogenides", University College London, London Centre for Nanotechnology, London, UK, June 15, 2016. | ||||||||||||||

"Frustrated Magnetism and Superconductivity in Iron Pnictides and Chalcogenides", University of Cologne, June 29, 2016. | ||||||||||||||

"Global Phase Diagram and Quantum Criticality of Heavy Fermion Metals and Kondo Insulators", International Conference on Strongly Correlated Electron SCES-2016, Hangzhou, China, May 9-13, 2016. | ||||||||||||||

"Iron-based Superconductivity and Strongly Correlated Electrons", Joint Workshop on Quantum Matter, Peking University, Beijing, Oct. 11, 2016. | ||||||||||||||

"Iron-based Superconductivity as a Prototype for Strongly Correlated Physics", Colloquium, Center for Nonlinear Studies, Los Alamos National Lab, Nov. 28, 2016. | ||||||||||||||

"Quantum Criticality -- from Heavy Fermion Metals to Kondo Insulator", Institute of Physics, Chinese Academy of Sciences, Beijing, China, Oct. 13, 2016. | ||||||||||||||

"Quantum Criticality and Superconductivity in Heavy Fermion Systems", Symposium Progress and New Directions on 4f Electron Materials, Rice University, Houston, Dec. 8, 2016. | ||||||||||||||

“Electron Correlations, Bad-Metal Behavior and Superconductivity in Iron Pnictides and Chalcogenides”,Frontiers of CMP Workshop, TRIUMF, Vancouver, May 16-21, 2015. | ||||||||||||||

“Frustrated Magnetism and Superconductivity in Iron Pnictides and Chalcogenides”, Joint Workshop on Novel Quantum Matter, Peking University, Beijing, Oct. 15, 2015. | ||||||||||||||

“Frustrated Magnetism and Superconductivity in Iron Pnictides and Chalcogenides”,Theoretical and Experimental Magnetism Meeting, Abingdon, UK, July 16-17, 2015. | ||||||||||||||

"Frustrated Magnetism and Superconductivity in Iron Pnictides and Chalcogenides", Workshop on Strongly Correlated Electron Materials, Rice University, Houston, Nov. 20, 2015. | ||||||||||||||

"High Temperature Superconductivity in Iron Pnictides and Chalcogenides", Columbia-Rice Frontiers of Condensed Matter Physics Lecture Series, Rice University, Houston, Dec. 1, 2015. | ||||||||||||||

“Local-Moment Magnetism, Quantum Criticality and Heavy Fermion Superconductivity”,Gordon Research Conference on Superconductivity, The Chinese University of Hong Kong, Hong Kong, May 24-29, 2015. | ||||||||||||||

“Magnetic Quantum Criticality and Heavy Fermion Superconductivity”, Electronic Structure Approaches and Applications to Quantum Matter, Santa Fe, New Mexico, May 18-21, 2015. | ||||||||||||||

“Quantum Criticality and Heavy-Fermion Superconductivity”, International Workshop on Heavy Fermions and Quantum Phase Transitions, Zhejiang University, Hangzhou, Apr. 15-17, 2015. | ||||||||||||||

“Quantum Criticality and Strongly Correlated Electrons”, Condensed Matter Seminar, Renmin University, Beijing, Jan. 7, 2015 | ||||||||||||||

“Quantum Criticality and the Kondo Lattice”, International School on Heavy Fermions and Quantum Phase Transitions, Zhejiang University, Hangzhou, Apr. 12-14, 2015 (three hours of lectures, part of a three-day school). | ||||||||||||||

“Superconductivity and Electron Correlations in the Iron Pnictides and Chalcogenides”, National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan, China, June 16, 2015. | ||||||||||||||

“Superconductivity and Electron Correlations in the Iron Pnictides and Chalcogenides”,Center of Advanced Quantum Studies, Beijing Normal University, Beijing, March 12, 2015. | ||||||||||||||

"Correlated Electrons and Quantum Materials", Physics Colloquium, Zhejiang University, Hangzhou, China, March 21, 2014. | ||||||||||||||

"Electron Correlations and Superconductivity in Iron Pnictides and Chalcogenides", Condensed Matter Seminar, University of California at Berkeley, Sept. 8, 2014. | ||||||||||||||

"Electron Correlations and Superconductivity in Iron Pnictides and Chalcogenides", Physics Institute Seminar, Karlsruhe Institute of Technology, Germany, June 23, 2014. | ||||||||||||||

"Electron Correlations and Superconductivity in the Iron Pnictides and Chalcogenides", Condensed Matter Seminar, University of Toronto, Oct. 3, 2014. | ||||||||||||||

"Electron correlations and Superconductivity in Iron Pnictides and Chalcogenides", Fourth International Conference on Superconductivity and Magnetism (ICSM 2014), Antalya, Turkey, Apr. 27-May 2, 2014. | ||||||||||||||

"Electron correlations and Superconductivity in Iron Pnictides and Chalcogenides", The 3rd Super-PIRE REMEI Workshop on Frontiers of Condensed Matter Physics, Beijing, China March 17-21, 2014. | ||||||||||||||

"Electron correlations and Superconductivity in Iron Pnictides and Chalcogenides", APS March Meeting, Denver, Colorado, March 3-7, 2014. | ||||||||||||||

"Electron correlations and Superconductivity in Iron Pnictides and Chalcogenides", 2014 EMN Conference on Iron- and Iridium-based Superconductivity, Cancun, Mexico, June 9-12, 2014. | ||||||||||||||

"Electron correlations and Superconductivity in Iron Pnictides and Chalcogenides", Beijing International Workshop (II) on Iron-based Superconductors, Institute of Physics, Beijing, China, Aug 4-7, 2014. | ||||||||||||||

"Electron correlations and superconductivity in the iron based superconductors", ICAM Summer School on New Developments in Condensed Matter Physics, Weihai, China, July 19-Aug 6, 2014. | ||||||||||||||

"Local Perspective on Non-Fermi Liquid, Quantum Criticality and Bad Metals", Aspen Center for Physics 2014 Winter Conference on Condensed Matter--Beyond Quasiparticles: New Paradigms for Quantum Fluids, Aspen, Colorado, Jan 12-18, 2014. | ||||||||||||||

"Quantum Criticality – How It Works, and How It Elucidates Electronic Matter", Physics Colloquium, University of Toronto, Oct. 2, 2014. | ||||||||||||||

"Quantum Criticality and Emergent Phases in Heavy Fermion Systems", Solid State Physics Colloquium, Max-Planck Institute for Chemical Physics of Solids, Dresden, Germany, June 5, 2014. | ||||||||||||||

"Quantum Criticality and Emergent Phases in Heavy Fermion Systems", Theoretical and Experimental Magnetism Meeting, Abingdon, UK, July 2-3, 2014. | ||||||||||||||

"Quantum Criticality and Emergent Phases in Kondo Lattice Systems", Conference on Non-Fermi Liquids, Stanford University, April 17-18, 2014. | ||||||||||||||

"Quantum Criticality, Emergent Phases and Strongly Correlated Electrons", Workshop on Quantum Critical Matter -- From Atoms to Bulk, Obergurgl Conference Center, Austria, Aug. 18-23, 2014. | ||||||||||||||

"Quantum Criticality, Emergent Phases and Strongly Correlated Electrons", Quantum Materials Perspectives and Opportunities: The Rice Center for Quantum Materials Launch Symposium, Rice University, Houston, Dec. 15-16, 2014. | ||||||||||||||

"Superconductivity based on Iron and Beyond: Towards a Conceptual Framework" Black Board Lunch Seminar, KITP, UC Santa Barbara, Nov. 17, 2014. | ||||||||||||||

"Electron Correlations and Superconductivity in Iron Pnictides and Chalcogenides", First Cross-Strait Workshop on Novel Quantum Materials, Hualien, Taiwan, Dec. 24-28, 2013. | ||||||||||||||

"Electronic Correlations and Quantum Criticality in Iron Pnictides", Sino-German (International) Workshop on Kondo and Mott Physics in Correlated Matter, Hangzhou, China, Oct. 14-17, 2013. | ||||||||||||||

"Orbital-Selective Mott Transition in Iron Pnictide Superconductors", Condensed Matter Science Colloquium, Los Alamos National Lab, Los Alamos, New Mexico, April 3, 2013 | ||||||||||||||

"Orbital-Selective Mott Transition in Iron Pnictide Superconductors", Seminar, University of Sherbrooke, Sherbrooke, Canada, April 11, 2013. | ||||||||||||||

"Orbital-selective Correlations and Neutron Resonance Excitations in Iron Pnictide Superconductors", Theoretical and Experimental Magnetism Meeting, Abingdon, UK, July 4-5, 2013 | ||||||||||||||

"Quantum Criticality -- from Chilled Antiferromagnets to Charged Black Holes", Physikalisches Kolloquium, Karlsruhe Institute of Technology, Germany, May 10, 2013. | ||||||||||||||

"Quantum Criticality and Emergent Phases in Heavy Fermion Metals", 2013 Hangzhou Workshop on Quantum Matter, Hangzhou, China, April 22-25, 2013. | ||||||||||||||

"Quantum Criticality and Strongly Correlated Electrons", Condensed Matter Seminar, University of California at Santa Cruz, Oct. 4, 2013. | ||||||||||||||

"Quantum Criticality and Unconventional Superconductivity", Colloquium, National Lab for Superconductivity, Institute of Physics, Chinese Academy of Sciences, Beijing, China, April 26, 2013. | ||||||||||||||

"Quantum Criticality and its Implications for Heavy Fermion Superconductivity", Spectroscopy on Novel Superconductors (SNS2013), Berkeley, California, June 24-28, 2013. | ||||||||||||||

"Quantum Criticality, Emergent Magnetic Phases and Superconductivity", DOE-CAS Heavy-Fermion Workshop, Los Alamos National Lab., New Mexico, Nov. 18-19, 2013 | ||||||||||||||

"Quantum Criticality, Magnetic Frustration and Emergent Phases in Heavy Fermion Metals", International Conference on Strongly Correlated Electron SCES-2013, Tokyo, Japan, Aug. 5-9, 2013. | ||||||||||||||

"Quantum Phase Transitions and Strongly Correlated Electrons", Physics Colloquium, Universite de Montreal, Montreal, Canada, April 12, 2013 | ||||||||||||||

"Quantum Phase Transitions in Heavy Fermion Metals and Kondo Insulators", Conference on Quantum Criticality: Experiment and Theory, Freudenstadt-Lauterbad, Germany, Sept. 15-19, 2013. | ||||||||||||||

"Quantum Phase Transitions in Heavy Fermion Metals and Kondo Insulators", Aspen Center for Physics Summer Workshop -- Disorder, Dynamics, Frustration and Topology in Quantum Condensed Matter, Aspen, CO, July 9, 2013. | ||||||||||||||

"Superconductivity on the Border of Magnetism: Heavy Fermions and Iron Pnictides", NORDITA Workshop on Superconductivity: the Second Century, Stockholm, Sweden, Aug. 20, 2013. | ||||||||||||||

"Correlated Electrons at the Border of Magnetism", Institute for Basic Science Symposium: From Observation of Quantum States in Solids to Their Control, Seoul, Korea, Sept. 6, 2012. | ||||||||||||||

"Entropy accumulation near quantum critical points", Workshop on Quantum Matter from the Nano- to the Macroscale, Max-Planck Institute for Physics of Complex Systems, Dresden, Germany, June 18-July 6, 2012. | ||||||||||||||

"Heavy Fermions and Quantum Phase Transitions: A Theorist's Perspective", International Workshop on Heavy Fermions and Quantum Phase Transitions, IOP, Beijing, China, Nov 10-12, 2012. | ||||||||||||||

"Local Quantum Criticality and Emergent Phases", Heavy Fermions Physics: Perspectives and Outlook, Beijing, China, Jan 7-9, 2012. | ||||||||||||||

"Magnetism and orbital-selective Mott physics in iron based superconductors", Theoretical and Experimental Magnetism Meeting, Abingdon, UK, June 28-29, 2012. | ||||||||||||||

"Orbital-Selective Mott Transition in Iron Pnictide Superconductors", University College London, London Centre for Nanotechnology, London, UK, May 30, 2012. | ||||||||||||||

"Orbital-Selective Mott Transition in Iron Pnictide Superconductors", Condensed matter seminar, Texas A&M University, College Station, TX, Oct. 5, 2012. | ||||||||||||||

"Quantum Criticality and Emergent Phases in Heavy Fermions", Condensed Matter Colloquium, Los Alamos National Lab, Los Alamos, New Mexico, March 21, 2012. | ||||||||||||||

"Quantum Criticality and Novel Phases", DARPA Workshop on Correlated Quantum Materials, Arlington, VA, Nov. 7-8, 2012. | ||||||||||||||

"Quantum Criticality and Strongly Correlated Electrons", Colloquium on Solid State Physics, TU Munich, Garching, Germany, Dec. 13, 2012. | ||||||||||||||

"Quantum Criticality, Non-Fermi Liquid and Unconventional Superconductivity", 19th International Conference on Magnetism (ICM2012), Busan, Korea, July 8-13, 2012. | ||||||||||||||

"Quantum magnetism of heavy fermions and effects of Berry phase", Workshop on Emergent Phases in Correlated and Topological Matter, Hangzhou, China, April 2-5, 2012. | ||||||||||||||

"Superconductivity, magnetic interactions and electron correlations in iron pnictides and selenides", Tenth International Conference on Materials and Mechanisms of Superconductivity (M2S 2012), Washington, D.C., USA, July 29-Aug. 3, 2012. | ||||||||||||||

"Theory Summary and Perspectives", International Conference on Quantum Criticality and Novel Phases (QCNP12), Dresden, Germany, Aug. 26-29, 2012. | ||||||||||||||

"Quantum Criticality and Emergent Phases", Condensed Matter Seminar, Charles University, Praha, Czech Republic, June 1, 2011. | ||||||||||||||

"The new iron chalcogenide (K,Tl)FexSe2: pairing strength and symmetries, and some general lessons about iron pnictides", Theoretical and Experimental Magnetism Meeting, Rutherford Appleton Laboratory, UK, June 16-17, 2011. | ||||||||||||||

"Electron Correlations and Superconductivity in Iron Pnictides and Selenides", 26th International Conference on Low Temperature Physics (LT26), Beijing, China, Aug. 10-17, 2011. | ||||||||||||||

"Electron Correlations and Superconductivity in Iron Pnictides and Selenides", International Workshop on Electronic Correlations in Models and Materials, Augsburg, Germany, Sept 11-15, 2011. | ||||||||||||||

"Electron Correlations and Superconductivity in the Iron Pnictides and Selenides", Condensed Matter Seminar, Harvard University, Cambridge, MA, Oct. 13, 2011. | ||||||||||||||

"Electron Correlations and Superconductivity in the Iron Pnictides and Selenides", Condensed Matter Seminar, UCLA, Los Angeles, CA, Nov. 9, 2011. | ||||||||||||||

"Local quantum criticality, Kondo lattice and holographic models of non-Fermi liquids", Black Hole Answers for Condensed Matter Questions, Lorentz center, Leiden, Netherlands, June 16, 2011. | ||||||||||||||

"Quantum Criticality and Emergent Phases", ERC Symposium Quantum Puzzle, Vienna, Austria, June 22, 2011. | ||||||||||||||

"Quantum Criticality and Emergent Phases", Institute Colloquium, Max-Planck Institute for Physics of Complex Systems, Dresden, Germany, April 18, 2011. | ||||||||||||||

"Quantum Criticality and Emergent Phases", Physikalisches Kolloquium, University Bonn, Germany, April 15, 2011. | ||||||||||||||

"Quantum Criticality and Strongly Correlated Electrons", Institute for Low Temperature and Structure Research, Polish Academy of Sciences, Wroclaw, Poland, Dec. 8, 2011. | ||||||||||||||

"Quantum Criticality and Strongly Correlated Electrons", Condensed Matter Seminar, University of Michigan, Ann Arbor, Oct. 11, 2011. | ||||||||||||||

"Quantum Criticality and Strongly Correlated Electrons", Chez Pierre Seminar, Massachusetts Institute of Technology, Cambridge, MA, Sept. 26, 2011. | ||||||||||||||

"Quantum Magnetism of Heavy Fermions and Effects of Berry Phases", Condensed matter seminar, Boston College, Boston, MA, Oct. 4, 2011. | ||||||||||||||

"Quantum critical points and emergent phases in heavy fermion metals", Workshop -- Developments and Prospects in Quantum Impurity Physics, Max-Planck Institute for Physics of Complex Systems, Dresden, Germany, June 5-June 10, 2011. | ||||||||||||||

"Quantum critical points and novel phases in heavy fermion metals", APS March Meeting, Dallas, Texas, March 21-25, 2011. | ||||||||||||||

"Quantum criticality and emergent phases in heavy fermion metals", Institute of Physics, Chinese Academy of Sciences, Beijing, China, Aug. 10, 2011. | ||||||||||||||

"The new iron chalcogenide (K,Tl)FexSe2: pairing strength and symmetries, and some general lessons about iron pnictides", International Institute of Physics (IIP) Workshop on Superconductivity, Natal/RN, Brazil, May 16-30, 2011. | ||||||||||||||

"Unconventional Superconductivity and Electron Correlations", Aspen Center for Physics Summer Workshop -- A New Century of Superconductivity: Iron Pnictides and Beyond, Aspen, CO, June 30, 2011. | ||||||||||||||

"Closing Comments -- Theoretical", International Conference on Strongly Correlated Electron SCES 2010, Santa Fe, NM, June 27-July 2, 2010. | ||||||||||||||

"Magnetism and Electron Correlations in Iron Pnictides", KITP Miniprogram on Iron-Based Superconductors, Kavli Institute for Theoretical Physics, UC Santa Barbara, January 10-21, 2011. | ||||||||||||||

"Magnetism and Superconductivity in the Iron Pnictides", Max-Planck Institute for Chemical Physics of Solids, Dresden, Germany, Feb 2, 2010. | ||||||||||||||

"Magnetism, Mott Localization and Superconductivity in Fe-based Caompounds", Theoretical and Experimental Magnetism Meeting, Institute of Physics, Abingdon, UK, Sept. 8-9, 2010. | ||||||||||||||

"Quantum Criticality and Global Phase Diagram of Heavy Fermion Metals", 2010 Hangzhou Workshop on Qunatum Matter, Hangzhou, China, May 18-21, 2010. | ||||||||||||||

"Quantum Criticality", Discussion Leader, 2010 Gordon Research Conference on Correlated Electron Systems, Mount Holyoke College, South Hadley, MA, June 13-18, 2010. | ||||||||||||||

"Quantum Criticality, Kondo Breakdown, and Fermi Surafces", DPG Spring Meeting, Regensburg, Germany, March 21-26, 2010. | ||||||||||||||

"Quantum Criticality: Many-Body Systems on the Brink", New Pictures of Strongly Correlated Electron Systems from Large Facilities -- Keith McEwen's 65th Birthday Celebration, University College London, June 4, 2010. | ||||||||||||||

"Quantum Phase Transitions and the Border of Magnetism", Physics Colloquium, University of Houston, Houston, Texas, Nov. 9, 2010. | ||||||||||||||

"Theoretical Aspects of the Iron Pnictides", International Conference on Magnetic Materials (ICMM 2010), Saha Institute of Nuclear Physics, Kolkata, India, Oct. 25-29, 2010. | ||||||||||||||

"Electronic Correlations and Magnetic Frustration in the Iron Pnictides", APS March Meeting, Pittsburgh, PA, March 16-20, 2009. | ||||||||||||||

"Electronic Correlations and Magnetic Frustration in the Iron Pnictides", KITPC Program on Iron-based High Tc Superconductors, Kavli Institute for Theoretical Physics China, Beijing, China, May 18-June 5, 2009. | ||||||||||||||

"Electronic Correlations and Magnetic Frustration in the Iron Pnictides", University College London, London Centre for Nanotechnology, London, UK, June 18, 2009. | ||||||||||||||

"Electronic Correlations and Magnetic Frustration in the Iron Pnictides", University of Cambridge, Department of Physics, Cavendish Laboratory, U.K., June 25, 2009. | ||||||||||||||

"Electronic Correlations and Magnetic Frustration in the Iron Pnictides'', University of Tokyo, Department of Applied Physics, Tokyo, Japan, May 20, 2009. | ||||||||||||||

"Fermi Surface and Magnetism in Heavy Fermion Metals", Technical University of Vienna, Austria, June 23, 2009. | ||||||||||||||

"Fermi Surface and Magnetism in Heavy Fermion Metals"; "Electronic Correlations and Magnetic Frustration in the Iron Pnictides" (two talks), Emergent Quantum Phenomena from the Nano to the Macro World, Cargese, Corsica, France, July 6-19, 2009. | ||||||||||||||

"Iron pnictides as a new setting for quantum criticality", Max-Planck Institute for Chemical Physics of Solids, Dresden, Germany, April 2, 2009. | ||||||||||||||

"Magnetism and Superconductivity in the Iron Pnictides", CCAST Workshop on Iron Based Superconductors, Beijing, China, Dec 5-6, 2009. | ||||||||||||||

"Magnetism and Superconductivity in the Iron Pnictides'', Kyoto University, Kyoto, Japan, Dec 10, 2009. | ||||||||||||||

"Magnetism and Superconductivity in the Iron Pnictides'', T-4 Seminar, Los Alamos National Lab, Los Alamos, New Mexico, Nov. 12, 2009. | ||||||||||||||

"Magnetism and Superconductivity in the Iron Pnictides", Theoretical and Experimental Magnetism Meeting, Institute of Physics, Abingdon, UK, July 2-3, 2009. | ||||||||||||||

"Quantum Criticality in Heavy Fermion Metals'', Condensed matter seminar, Texas A&M University, College Station, TX, Oct. 2, 2009. | ||||||||||||||

"Quantum Criticality out of Equilibrium", KITP Program on Low Dimensional Electron Systems, KITP, UC Santa Barbara, May 7, 2009. | ||||||||||||||

"Quantum Criticality, Kondo Effect, and Fermi Surfaces", University of Tokyo, Institute for Solid State Physics, Tokyo, Kashiwa, Chiba, May 19, 2009. | ||||||||||||||

"Quantum Many-Body Physics and Strongly Correlated Electron Systems'', Physics Colloquium, Beihang University, Beijing, China, Dec 8, 2009. | ||||||||||||||

"Superconductivity in the Iron Age'', Colloquium, Department of Physics and Astronomy, Rice University, Houston, TX, Sept. 2, 2009. | ||||||||||||||

"Theoretical Overview", Aspen Center for Physics Summer Workshop on Correlated Behavior and Quantum Criticality in Heavy Fermion and related Systems, Aspen, CO, August 11, 2009. | ||||||||||||||

"Towards a Global Phase Diagram of Magnetic Heavy Fermions", Hangzhou Workshop on Quantum Matter, Hangzhou, China, Oct. 12-15, 2009. | ||||||||||||||

"What is Going on in the Iron Pnictides", TcSUH, University of Houston, April 9, 2009. | ||||||||||||||

"Are Iron Pnictides Strongly Correlated." Aspen Center for Physics Summer Workshop on Frontiers of Strongly Correlated Electrons, Aspen, CO. (Aug 7, 2008) | ||||||||||||||

"Electronic Correlations and Magnetic Frustration in the Iron Pnictides." Condensed matter seminar, Iowa State University, Ames, Iowa. (Sept 25, 2008) | ||||||||||||||

"Electronic Correlations and Magnetic Frustration in the Iron Pnictides." Beijing International Workshop on Iron-(Nickel)-based Superconductors, Institute of Physics, Chinese Academy of Sciences, Beijing, China. (Oct 17-19, 2008) | ||||||||||||||

"Fermi Surface and Magnetism in Kondo Lattice Systems." Workshop on Unconventional Phases and Phase Transitions in Strongly Correlated Electron Systems, Max-Planck Institute for Physics of Complex Systems, Dresden, Germany. (June 2-27, 2008) | ||||||||||||||

"Fermi Surface and Magnetism in the Kondo Lattice." 2008 Gordon Research Conference on Correlated Electron Systems, New Biddeford, Maine. (June 8-13, 2008) | ||||||||||||||

"Magnetism and Quantum Criticality in Heavy Fermions and Iron Pnictides." ICAM/DCHEM Workshop on Emergent Behavior in Heavy Electron Materials, Aspen, CO. (Aug 28, 2008) | ||||||||||||||

"Magnetism in Heavy Fermions and Iron Pnictides." Theoretical and Experimental Magnetism Meeting, Institute of Physics, Abingdon, UK. (July 31-August 1, 2008) | ||||||||||||||

"Quantum Criticality beyond Order-Parameter Fluctuations." Aspen Center for Physics 2008 Winter Conference on Condensed Matter: New Horizons in Condensed matter Physics, Aspen, CO. (Feb 3-9, 2008) | ||||||||||||||

"Strongly Correlated Electron Systems." Second International Vienna Symposium on Functional Matter: From designer materials to quantum technologies, TU-Wien, Austria. (June 27, 2008) | ||||||||||||||

"Strongly Correlated Electrons: from Quantum Criticality to the High Tc Iron Pnictides." Institute of Physics, CAS, Beijing, China. (May 19, 2008) | ||||||||||||||

"Strongly Correlated Electrons: from Quantum Criticality to the High Tc Iron Pnictides." University of Science and Technology of China, Hefei, China. (April 29, 2008) | ||||||||||||||

"Strongly Correlated Electrons: from Quantum Criticality to the High Tc Iron Pnictides." Physics Colloquium, Zhejiang University, Hangzhou,China. (May 6, 2008) | ||||||||||||||

"Strongly Correlated Electrons: from Quantum Criticality to the High Tc Iron Pnictides." Fudan University, Shanghai, China. (May 8, 2008) | ||||||||||||||

"Strongly Correlated Electrons: from Quantum Criticality to the High Tc Iron Pnictides." Center for Advanced Studies, Tsinghua University, Beijing, China. (May 15, 2008) | ||||||||||||||

"Summary Discussion." ICAM Workshop on Fe-pnictide and Related Superconductors, College Park, Maryland. (Nov 16-17, 2008) | ||||||||||||||

"Fermi Surface and Antiferromagnetism in Kondo Lattice Systems." Max-Planck Institute for Chemical Physics of Solids, Dresden, Germany. (Feb 12, 2007) | ||||||||||||||

"Heavy fermion quantum criticality: Fermi surface and multiple energy scales." Frontiers of Condensed Matter -- Celebrating the research achievements of Elihu Abrahams, Rutgers University, Piscataway, NJ. (April 20-22, 2007) | ||||||||||||||

"Local Quantum Criticality: from Heavy Fermions to Magnetic Nanostructures." New Frontiers in Quantum Impurity Physics: From Nano-Structures to Molecular Devices, Max-Planck Institute for Physics of Complex Systems, Dresden, Germany. (August 13-24, 2007) | ||||||||||||||

"Local Quantum Criticality: from Heavy Fermions to Nanodevices." NHMFL, Florida State University, Tallahassee, Florida. (Sept 26, 2007) | ||||||||||||||

"Local Quantum Criticality: from Heavy Fermions to Nanostructures." Physics Colloquium, Zhejiang University, Hangzhou, China. (July 2, 2007) | ||||||||||||||

"Quantum Criticality and Fermi Surfaces." KITP Program on Strongly Correlated Phases in Condensed Matter and Degenerate Atomic Systems, KITP, UC Santa Barbara, CA. (April 12, 2007) | ||||||||||||||

"Quantum Criticality and Fermi Surfaces." KITPC Program on Quantum Phases of Matter, Kavli Institute for Theoretical Physics China, Beijing, China. (July 6, 2007) | ||||||||||||||

"Quantum Criticality and Strongly Correlated Electrons." Condensed Matter Colloquium, Los Alamos National Lab, Los Alamos, NM. (Oct 3, 2007) | ||||||||||||||

"Quantum Criticality and Superconductivity in Heavy Fermions." Aspen Center for Physics Summer Workshop on Novel Aspects of Superconductivity, Aspen, CO. (July 21, 2007) | ||||||||||||||

"Quantum Criticality in Correlated Matter." Physics Colloqium, Dartmouth College, Hanover, New Hampshire. (Jan 26, 2007) | ||||||||||||||

"Quantum Criticality in Kondo Lattices." ICAM Workshop on 1-1-5 Materials: The Rosetta Stone for the Kondo Lattice, Aspen, CO. (Aug 4, 2007) | ||||||||||||||

"Quantum Criticality of Heavy Fermion Metals: Thermodynamic Aspects." National High Magnetic Field Lab, Tallahassee, Florida. (Sept. 27, 2007) | ||||||||||||||

"Quantum Criticality, Kondo Effect and Fermi Surfaces." Homage to Daniel Grempel Memorial Conference, CEA-Saclay, France. (June 14-15, 2007) | ||||||||||||||

"Quantum Fluctuations, Criticality, and Strongly Correlated Electrons." Workshop on Future Directions in Interacting Electron Physics, Austin, Texas. (Octt 11, 2007) | ||||||||||||||

"Quantum Phases and their Transitions in Magnetic Heavy Fermions." The Heavy Fermion Frontier: a Workshop in Honor of Joe D. Thompson's 60th Birthday, Santa Fe, New Mexico. (Nov 12, 2007) | ||||||||||||||

"Global Phase Diagram and Quantum Criticality in Magnetic Heavy Fermion Metals." International Conference on Magnetism (ICM2006), Kyoto, Japan. (Aug 20-25, 2006) | ||||||||||||||

"Quantum Critical Point beyond Order-Parameter Fluctuations -- the Case of Heavy Fermion Metals." Condensed Matter Seminar, University of California at Riverside, Riverside, CA. (April 12, 2006) | ||||||||||||||

"Quantum Criticality." Hangzhou Workshop on Quantum Matter, Hangzhou, China. (Oct 16-19, 2006) | ||||||||||||||

"Quantum Criticality." Condensed Matter Seminar, University of Virginia, Charlottesville, Virginia. (Sept 28, 2006) | ||||||||||||||

"Quantum Criticality and Fermi-Surface Transformation." Eighth International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors (M2S-VIII), Dresden, Germany. (July 9-14, 2006) | ||||||||||||||

"Quantum Phase Transition and non-Fermi Liquid Behavior." International Conference on Physics Education and Frontier Physics, Taipei, Taiwan. (June 27-30, 2006) | ||||||||||||||

"Quantum Phase Transitions and Strongly Correlated Electrons." Physics Colloquium, University of Science and Technology of China, Hefei, China. (July 3, 2006) | ||||||||||||||

"Local Quantum Criticality and Fermi-Surface Transformation." Theoretical and Experimental Magnetism Meeting, Institute of Physics and ISIS/CCLRC, Abingdon, UK. (August 2-3, 2005) | ||||||||||||||

"Phenomenological Aspects of Local Quantum Criticality." Fifth International Symposium on Advanced Science Research --Advances in the Physics and Chemistry of Actinide Compounds, JAERI Tokai, Ibaraki, Japan (cancelled due to Hurricane Rita). (Sept. 27-29, 2005) | ||||||||||||||

"Quantum Criticality in Kondo Systems." Aspen Center for Physics Summer Workshop on Gauge Theories and Fractionalization in Correlated Quantum Matter, Aspen, CO. (August 9, 2005) | ||||||||||||||

"Quantum Phase Transition and non-Fermi Liquid Behavior." Conference on Physical Phenomena at High Magnetic Fields-V, National High Magnetic Field Laboratory, Tallahassee, Florida. (August 5-9, 2005) | ||||||||||||||

"Quantum Phase Transitions and Correlated Electrons." University College London, London, UK. (March 10, 2005) | ||||||||||||||

"Quantum Phase Transitions and Strongly Correlated Electrons." I2CAM Workshop on Chemical Physics of Complex Adaptive Matter, Ringberg Castle (Bavaria), Germany. (February 6 - 9, 2005) | ||||||||||||||

"Quantum Phase Transitions and Strongly Correlated Electrons." PHYSICS COLLOQUIUM, Zhejiang University, Hangzhou, China. (Dec. 9, 2005) | ||||||||||||||

"The Global Phase Diagram of Magnetic Heavy Fermion Metals." Joint Workshop of NQP (New Quantum Phenomena)-skutterudites and NPM (New Phase of Matter) in multi-approach, Tokyo Metropolitan University, Hachioji, Tokyo. (November 21- 24, 2005) | ||||||||||||||

"Two talks: 1) Kondo lattices: What do we learn from microscopics? 2) Heavy fermion metals: Global phase diagram, local quantum criticality, and experiments." Workshop on Emergent Quantum Phases in Strongly Correlated Electron Systems, Korea Institute for Advanced Study (KIAS), Seoul, Korea. (October 24-29, 2005) | ||||||||||||||

"Exotic Quantum Criticality in Kondo Lattices." KITP Program on Exotic Order and Criticality in Quantum Matter, KITP, UCSB. (June 30, 2004) | ||||||||||||||

"Extended DMFT Study of Kondo Lattices." Workshop on Quantum Criticality and Dynamical Mean Field Theory, SPhT/CEA-Saclay, France. (Dec 7, 2004) | ||||||||||||||

"Hall Effect and Fermi Surface Fluctuations near Quantum Critical Points." Theory Seminar, University of karlsruhe, Karlsruhe, Germany. (Feb, 2004) | ||||||||||||||

"Local Quantum Critical Points: from Correlated Matters to Mesoscopic Structures." Condensed Matter Seminar, University of Sherbrooke, Sherbrooke, Canana. (March, 2004) | ||||||||||||||

"Local Quantum Criticality and Fermi-surface Fluctuations." International Workshop on Materials Science and Nano-Engineering, Osaka, Japan. (Dec 10-14, 2004) | ||||||||||||||

"Local Quantum Criticality and non-Fermi Liquid Properties." DPG (Germany Physical Society) Spring Meeting, Regensburg, Germany. (March 8-12, 2004) | ||||||||||||||

"Local Quantum Criticality and non-Fermi Liquid Properties." ICTP Workshop on Novel States and Phase Transitions in Highly Correlated Matter, Trieste, Italy. (July 12-23, 2004) | ||||||||||||||

"Local Quantum Criticality and non-Fermi Liquid Properties." American Physical Society March Meeting, Montreal, Quebec, Canada. (March 22-26, 2004) | ||||||||||||||

"Quantum Critical Metals: beyond Order Parameter Fluctuations." International Workshop on Evolution of Quantum Effects from the Nano-to the Macroscale, Cargese, Corsica, France. (May 17-22, 2004) | ||||||||||||||

"Quantum Criticality in Kondo Systems." YKIS 2004 Physics of Strongly Correlated Electron Systems, Yukawa Institute, Kyoto, Japan. (Nov 12-19, 2004) | ||||||||||||||

"Quantum Phase Transitions and non-Fermi Liquid Phenomena." WE-Heraeus-Seminar on Quantum Phase Transitions, Bad Honnef, Germany. (October 10-14, 2004) | ||||||||||||||

"Quantum Phase Transitions in Kondo Impurities and in Mesoscopic Structures." Condensed Matter Seminar, Cologne University. (Oct 8, 2004) | ||||||||||||||

"TURNING UP THE HEAT AT ZERO TEMPERATURE: Quantum Phase Transitions and non-Fermi Liquids." Physics Colloquium, Rice University. (Nov 10, 2004) | ||||||||||||||

"TURNING UP THE HEAT AT ZERO TEMPERATURE: Quantum Phase Transitions and non-Fermi Liquids." Physics Colloquium, Louisiana State University. (Oct 28, 2004) | ||||||||||||||

Keynote Speaker | ||||||||||||||

"Quantum Criticality and Strongly Correlated Electrons", 27th International Conference on Low Temperature Physics (LT27), Semi-PLENARY TALK, Buenos Aires, Argentina, Aug. 6-13, 2014. | ||||||||||||||

"Magnetism in metals on the verge of Mott transition and quantum criticality in parent pnictides", Keynote Speaker, SEPnet Summer Program: Condensed Matter Physics in the City, London, UK, June 13-14, 2011. | ||||||||||||||

"Quantum Criticality, Kondo Breakdown, and Fermi Surfaces", PLENARY TALK, International Conference on Quantum Criticality and Novel Phases (QCNP09), Dresden, Germany, Aug. 2-5, 2009. | ||||||||||||||

"Quantum Criticality and Fermi Surface Transformation." PLENARY TALK, International Conference on Strongly Correlated Electron SCES'05, Vienna, Austria. (July 26 - 30, 2005) | ||||||||||||||

Lectures | ||||||||||||||

"Quantum Criticality and Heavy Fermion Physics", Columbia-Rice Frontiers of Condensed Matter Physics Lecture Series, Rice University, Houston, Oct. 22 and 24, 2013 (two lectures). | ||||||||||||||

"Quantum Criticality and Strongly Correlated Fermions", Bethe Colloquium, University Bonn, Germany, May 6, 2013. | ||||||||||||||

"Quantum Criticality and The Kondo Lattice", Second Fudan Summer School for Condensed Matter Physics -- Quantum Phase Transitions, July 19-22, 2012 (summer school lectures, 4 days, 8 hrs). | ||||||||||||||

"Kondo Problem to Heavy Fermions and Local Quantum Criticality", Advanced School -- Developments and Prospects in Quantum Impurity Physics, Max-Planck Institute for Physics of Complex Systems, Dresden, Germany, May 30-June 3, 2011. | ||||||||||||||

"Magnetism, Localization and Superconductivity", Inaugural Lecture of Changhiang Professorship, Zhejiang University, Hangzhou, China, Oct. 22, 2010. | ||||||||||||||

"Quantum Criticality and Heavy Fermions", Tutorial lecture, Post-Workshop Tutorial-- 2010 Hangzhou Workshop on Qunatum Matter, Hangzhou, China, May 22, 2010. | ||||||||||||||

"Strongly Correlated Electrons: from Quantum Criticality to the High Tc Iron Pnictides." Frontiers in Chemical Physics of Solids Lecture, Max-Planck Institute for Physics of Complex Systems, Dresden, Germany. (June 19, 2008) | ||||||||||||||

Editorial Positions | ||||||||||||||

Member of the Editorial Board, Journal of Physics: Condensed Matters. IOP. (2002 - 2006) | ||||||||||||||

Supervised Theses & Dissertations | ||||||||||||||

Seiji J Yamamoto, Ph.D Magnetism and Fermi Surface in Heavy Fermion Metals. (2009) (Thesis Director) | ||||||||||||||

Jianda Wu, Ph.D. "Research on Dynamics and Thermodynamics near Quantum Critical Points. (2014) (Thesis Director) | ||||||||||||||

Aditia Shashi, Ph.D. Exploring aspects of nonequilibrium physics with quantum impurity problems. (2014) (Thesis Co-Director) | ||||||||||||||

Jed Pixley, Ph.D. Quantum Criticality in Heavy Fermion Metals and a New Route to Superconductivity. (2014) (Thesis Director) | ||||||||||||||

Emilian Nica, Ph.D. Strongly correlated electron systems: From quantum criticality in heavy-fermion metals to orbital-dependent superconductivity in Fe-based materials. (2016) (Thesis Director) | ||||||||||||||

Tal Einav, B.S. Iron pnictides superconductivity. (Thesis Director) | ||||||||||||||

Awards, Prizes, & Fellowships | ||||||||||||||

Humboldt Prize, Alexander von Humboldt Foundation (2013-2014) | ||||||||||||||

Bethe Colloquium, University of Bonn, Germany (May 2013) | ||||||||||||||

Qianren Short Term Visiting Professor, Institute of Physics, Chinese Academy of Sciences (2012-2015) | ||||||||||||||

Changjiang Chair Professor, China's Ministry of Education (2010-2012), | ||||||||||||||

Fellow, American Association for the Advancement of Science (since 2008), | ||||||||||||||

Frontiers in Chemical Physics of Solids Lecture (Max-Planck Institute-CPfS, 2008), Max-Planck Institute - CPfS, Dresden, Germany (2008) | ||||||||||||||

Co-Chairman, SCES'07 (2007 International Conference on Strongly Correlated Electron Systems), Houston, May 2007, (May, 2007) | ||||||||||||||

Fellow, American Physical Society (since 2005), (2005) | ||||||||||||||

Fellow, Institute of Physics, UK (since 2004), | ||||||||||||||

Alfred P. Sloan Research Fellow, (96-00) | ||||||||||||||

Cottrell Scholar Award, Research Corporation (98-03) | ||||||||||||||

Positions Held | ||||||||||||||

General Member, Aspen Center for Physics, Aspen Center for Physics. (2009 - 2019) | ||||||||||||||

Corresponding Member (since 2011), Journal Club for Condensed Matter Physics. (2011 - 2018) | ||||||||||||||

Visiting Professor, University of California, Berkeley. (2017 - 2017) | ||||||||||||||

Humboldt Research Award Visiting Professor, Karlsruhe Institute of Technology. (2013 - 2014) | ||||||||||||||

Director, Rice Center for Quantum Materials (since 2014). (2014 - 2018) | ||||||||||||||

Visiting Associate Professor, Dept of Physics, University of Illinois at Urbana-Champaign. (2002 - 2002) |