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Scholarly Interest Report
Pengcheng Dai
Professor of Physics and Astronomy
  • Ph.D experimental condensed matter physics (1993) University of Missouri-Columbia, Columbia, Missouri
  • B.S. Physics (1984) Zhengzhou University, Zhengzhou, China
Primary Department
   Department of Physics and Astronomy
Department Affiliations
  • Department of Physics and Astronomy
     Pengcheng Dai's group
     Pengcheng Dai's group
     Dai group home page
    Research Areas
     Experimental condensed matter physics, using neutron as a probe to study correlated electron materials.

    Using neutron as a probe to study correlated electron materials


    It is well-known that band filling in noninteracting or weakly interacting electron systems determines its electrical transport properties.  An insulator has a completely filled electrons at the highest filled band while a metal has a partially filled band.  For these materials, the metal-insulator transition (MIT) occurs through tuning the top-level electron occupation.  However, for strongly electron interacting systems such as many transition metal oxides (TMOs) with a partially filled d-band, a large Coulomb repulsion between the outer most d-electrons on the same lattice site would split the highest filled band into two: the lower one (lower Hubbard band) corresponds to single electron occupation while the upper one (upper Hubbard band) to double occupation.  With exactly one electron per site (half-filled), the lower Hubbard band is full, and the system forms an insulating state called the Mott insulator.  Most Mott insulators have AF long-range order at zero temperature due to Heisenberg coupling between neighboring spins.  Once a Mott insulator is doped away from the half-filled case, the system should in principle become metallic.  However, strong coupling among spin, charge, and orbital degrees of freedom often makes this regime an anomalous metallic phase which exhibits many unusual physical phenomena such as high-Tc superconductivity, CMR effect and etc.


    Understanding how MIT occurs in TMOs poses one of the most profound intellectual challenges in the physical sciences today.  This is because TMOs are often characterized by physical complexity resulting from the coexistence and competition between different kind of order involving charge, orbital, lattice, and spin degrees of freedom.  The relationship between these degrees of freedom is often synergistic and non-linear.  The complexity of TMOs is directly responsible for their tunability.


    Neutrons—with their wavelengths and energies comparable to atomic spacing and lattice vibrations in solids—have played a unique role in determining the static and dynamic lattice and magnetic properties of the TMOs. Some of the reasons for this are as follows: 1) Neutrons are scattered by the nucleus. Light atoms such as hydrogen and oxygen scatter just as strongly as heavier atoms. 2) The neutron carries a magnetic moment that interacts with localized magnetic ions and unpaired itinerant electrons in solids. 3) Neutron is a weak interacting probe. Neutron scattering cross section is determined by the static and dynamic correlation functions of the system, without the need for correcting the influence of the probe. 4) Neutrons are a highly penetrating bulk probe and therefore insensitive to surface imperfections.


    The central aim of our group is to use neutron scattering as a technique to study magnetic properties of correlated electron materials, essentially to understand why materials behave the way they do and how electron correlations can affect the bulk properties of these materials.

    Selected Publications
     Refereed articles

    B. J. Campbell, S. Rosenkranz, H. J. Kang, H. T. Stokes, P. J. Chupas, S. Komiya, Y. Ando, Shiliang Li, and Pengcheng Dai "Long-range two-dimensional superstructure in the superconducting electron-doped cuprate Pr0.88LaCe0.12CuO4." Phys. Rev. B, 92 (2015) : 014118.


    Chenglin Zhang, 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 NaFe0.985Co0.015 ." Phys. Rev. B , 91 (2015) : 104520.


    Ding Hu, Xingye Lu, Wenliang Zhang, Huiqian Luo, Shiliang Li, Peipei Wang, Genfu Chen, Fei Han, Shree R. Banjara, A. Sapkota, A. Kreyssig, A. I. Goldman, Z. Yamani, Christof Niedermayer, Markos Skoulatos, Robert Georgii, T. Keller, Pengshuai Wang, Weiqiang Yu, and Pengcheng Dai "Structural and Magnetic Phase Transitions near Optimal Superconductivity in BaFe2As1?xPx-2 ." Phys. Rev. Lett., 114 (2015) : 157002.


    Haoran Man, Xingye Lu, Justin S. Chen, Rui Zhang, Wenliang Zhang, Huiqian Luo, J. Kulda, A. Ivanov, T. Keller, Emilia Morosan, Qimiao Si, and Pengcheng Dai "Electronic nematic correlations in the stress-free tetragonal state of BaFe2?xNixAs2." Phys. Rev. B, 92 (2015) : 134521.


    Justin S. Chen, Jiakui K. Wang, Scott V. Carr, Sven C. Vogel, Olivier Gourdon, Pengcheng Dai, and E. Morosan "Chemical tuning of electrical transport in Ti1-xPtxSe2-y ." Phys. Rev. B , 91 (2015) : 045125.


    Mahmoud Abdel-Hafiez, Yuanyuan Zhang, Zheng He, Jun Zhao, Christoph Bergmann, Cornelius Krellner, Chun-Gang Duan, Xingye Lu, Huiqian Luo, Pengcheng Dai, and Xiao-Jia Chen "Nodeless superconductivity in the presence of spin-density wave in pnictide superconductors: The case of BaFe2-xNixAs2 ." Phys. Rev. B, 90 (2014) : 144502.


    Meng Wang, P. Valdivia, Ming Yi, J. X. Chen, W. L. Zhang, R. A. Ewings, T. G. Perring, Yang Zhao, L. W. Harriger, J. W. Lynn, E. Bourret-Courchesne, Pengcheng Dai, D. H. Lee, D. X. Yao, and R. J. Birgeneau " Spin waves and spatially anisotropic exchange interactions in the S = 2 stripe antiferromagnet Rb0.8Fe1.5S2 ." Phys. Rev. B, 92 (2015) : 041109(R).


    Meng Wang,Ming Yi, Huibo Cao, C. de la Cruz, S. K. Mo, Q. Z. Huang, E. Bourret-Courchesne, Pengcheng Dai, D. H. Lee, Z. X. Shen, and R. J. Birgeneau "Mott localization in a pure stripe antiferromagnet Rb1??Fe1.5??S2." Phys. Rev. B, 92 (2015) : 121101.


    Pengcheng Dai "Antiferromagnetic order and spin dynamics in iron-based superconductors." Rev. Mod. Phys., 87 (2015) : 855.


    Rui Zhang, Dongliang Gong, Xingye Lu, Shiliang Li, Mark Laver, Christof Niedermayer, Sergey Danilkin, Guochu Deng, Pengcheng Dai, and Huiqian Luo "Doping evolution of antiferromagnetism and transport properties in nonsuperconducting BaFe$_{2-2x}$Ni$_x$Cr$_x$As$_2$ ." Phys. Rev. B, 91 (2015) : 094506.


    S. Y. Tan, J. Jiang, Z. R. Ye, X. H. Niu, Y. Song, C. L. Zhang, P. C. Dai, B. P. Xie, X. C. Lai, and D. L. Feng "Photoemission study of the electronic structure and charge density waves of Na2Ti2Sb2O ." Scientific Reports , 5 (2015) : 9515.


    Xiao Ren, Lian Duan, Yuwen Hu, Jiarui Li, Rui Zhang, Huiqian Luo, Pengcheng Dai, and Yuan Li " Nematic Crossover in BaFe2As2 under Uniaxial Stress ." Phys. Rev. Lett., 115 (2015) : 197002.


    Yu Song, Xingye Lu, D. L. Abernathy, David W. Tam, J. L. Niedziela, Wei Tian, Huiqian Luo, Qimiao Si, and Pengcheng Dai " Energy dependence of the spin excitation anisotropy in uniaxial-strained BaFe1.9Ni0.1As2 ." Phys. Rev. B, 92 (2015) : 180504.


    H. Kim, M. A. Tanatar, Yong Liu, Z. C. Sims, Chenglin Zhang, Pengcheng Dai, T. A. Lograsso, and R. Prozorov "Evolution of London penetration depth with scattering in single crystals of K1?xNaxFe2As2." Phys. Rev. B, 89 (2014) : 174519.


    Chenglin Zhang, Leland W. Harriger, Zhiping Yin, Weicheng Lv, Miaoyin Wang, Guotai Tan, Yu Song, D. L. Abernathy, Wei Tian, Takeshi Egami, Kristjan Haule, Gabriel Kotliar, and Pengcheng Dai "Effect of Pnictogen Height on Spin Waves in Iron Pnictides." Phys. Rev. Lett., 112 (2014) : 217202.


    Chenglin Zhang, Yu Song, L.-P. Regnault, Yixi Su, M. Enderle, J. Kulda, Guotai Tan, Zachary C. Sims, Takeshi Egami, Qimiao Si, and Pengcheng Dai "Anisotropic neutron spin resonance in underdoped superconducting NaFe1?xCoxAs." Phys. Rev. B , 90 (2014) : 140502(R).


    Long Ma, J. Dai, P. S. Wang, X. R. Lu, Yu Song, Chenglin Zhang, G. T. Tan, Pengcheng Dai, D. Hu, S. L. Li, B. Normand, and Weiqiang Yu "Phase separation, competition, and volume-fraction control in NaFe1?xCoxAs." Phys. Rev. B , 90 (2014) : 144502.


    Meng Wang, Wei Tian, P. Valdivia, Songxue Chi, E. Bourret-Courchesne, Pengcheng Dai, and R. J. Birgeneau "Two spatially separated phases in semiconducting Rb0.8Fe1.5S2." Phys. Rev. B , 90 (2014) : 125148.


    P. Zhang, P. Richard, T. Qian, X. Shi, J. Ma, L.-K. Zeng, X.-P. Wang, E. Rienks, C.-L. Zhang, Pengcheng Dai, Y.-Z. You, Z.-Y. Weng, X.-X. Wu, J. P. Hu, and H. Ding "Observation of Momentum-Confined In-Gap Impurity State in Ba0.6K0.4Fe2As2: Evidence for Antiphase s+- Pairing." Phys. Rev. X, 4 (2014) : 031001.


    Rui Zhang, Dongliang Gong, Xingye Lu, Shiliang Li, Pengcheng Dai, and Huiqian Luo "The effect of Cr impurity to superconductivity in electron-doped BaFe2?xNixAs2." Supercond. Sci. Technol, 27 (2014) : 115003.


    Scott V. Carr, Despina Louca, Joan Siewenie, Q. Huang, Aifeng Wang, Xianhui Chen, and Pengcheng Dai "Structure and composition of the superconducting phase in alkali iron selenide KyFe1.6+xSe2." Phys. Rev. B , 89 (2014) : 134509.


    W. Tian, Guotai Tan, Liu Liu, Jinxing Zhang, Barry Winn, Tao Hong, J. A. Fernandez-Baca, Chenglin Zhang, and Pengcheng Dai "Influence of doping on the spin dynamics and magnetoelectric effect in hexagonal Y0.7Lu0.3MnO3 ." Phys. Rev. B , 89 (2014) : 144417.


    Xianhui Chen, Pengcheng Dai, Donglai Feng, Tao Xiang, and Fu-Chun Zhang "Iron-based high transition temperature superconductors." National Science Review, 1 (2014) : 371.

    doi: 10.1093/nsr/nwu007

    Xingye Lu, David W. Tam, Chenglin Zhang, Huiqian Luo, Meng Wang, Rui Zhang, Leland W. Harriger, T. Keller, B. Keimer, L.-P. Regnault, Thomas A. Maier, and Pengcheng Dai "Short-range cluster spin glass near optimal superconductivity in BaFe2?xNixAs2." Phys. Rev. B , 90 (2014) : 024509 .


    Xingye Lu, J. T. Park, Rui Zhang, Huiqian Luo, Andriy H. Nevidomskyy, Qimiao Si, Pengcheng Dai "Nematic spin correlations in the tetragonal state of uniaxial-strained BaFe_{2-x}Ni_{x}As_2." Science, 345 (2014) : 657.


    Phys. Rev. B 88, 064504 (2013).


    Phys. Rev. B 87, 081101 (2013).


    Phys. Rev. Lett. 111, 207002 (2013). 


    Phys. Rev. X 3, 041036 (2013)


    Phys. Rev. Lett. 111, 107004 (2013).


    Phys. Rev. B 87, 144512 (2013).


    Phys. Rev. Lett. 111, 107006 (2013).


    Phys. Rev. B 88, 144516 (2013).


    Phys. Rev. B 88, 184514(2013).


    Nature Communications 4, 1470 (2013).


    Journal of Physics: Condensed Matter 25, 395702 (2013). 


    Nature Communications 4, 2874 (2013).


    Phys. Rev. B 87, 064409 (2013).


    Nature Physics 8, 709 (2012).


    Phys. Rev. X 3, 011020 (2013).


    Phys. Rev. B 88, 134518 (2013).


    Phys. Rev. B 87, 174517 (2013).


    Phys. Rev. Lett. 110, 257001 (2013).


    Phys. Rev. B 88, 134512 (2013).


    Phys. Rev. B 87, 184511 (2013).


    Nature Physics 9, 42 (2013).


    Phys. Rev. Lett. 108, 247002 (2012).


    Phys. Rev. Lett. 108, 227002 (2012).


    Phys. Rev. B 86, 140403 (2012).


    Nature Physics 8, 376 (2012).

     Book chapters

    Yu Song and Pengcheng Dai "High-Temperature Superconductors." Experimental Methods in the Physical Sciences, 48 (2015) : 145-201.


    Charnukha, A; Yin, ZP; Song, Y; Cao, CD; Dai, Pengcheng; Haule, K; Kotliar, G; Basov, DN; "Correlation-driven metal-insulator transition in proximity to an iron-based superconductor." Physical Review B, 96 (2017) : 195121.Unknown


    Chen, Zhi-Guo; Wang, Luyang; Song, Yu; Lu, Xingye; Luo, Huiqian; Zhang, Chenglin; Dai, Pengcheng; Yin, Zhiping; Haule, Kristjan; Kotliar, Gabriel; "Two-Dimensional Massless Dirac Fermions in Antiferromagnetic A Fe 2 As 2 (A= Ba, Sr)." Physical review letters, 119 (2017) : 96401.Unknown


    Gannon, WJ; Halperin, WP; Eskildsen, MR; Dai, Pengcheng; Hansen, UB; Lefmann, K; Stunault, A; "Spin susceptibility of the topological superconductor UPt 3 from polarized neutron diffraction." Physical Review B, 96 (2017) : 41111.Unknown


    Hu, Ding; Zhang, Wenliang; Wei, Yuan; Roessli, Bertrand; Skoulatos, Markos; Regnault, Louis Pierre; Chen, Genfu; Song, Yu; Luo, Huiqian; Li, Shiliang; "Spin excitation anisotropy in the optimally isovalent-doped superconductor BaFe 2 (As 0.7 P 0.3) 2." Physical Review B, 96 (2017) : 180503.Unknown


    Li, Yu; Wang, Weiyi; Song, Yu; Man, Haoran; Lu, Xingye; Bourdarot, Fr真d真ric; Dai, Pengcheng; "Spin excitation anisotropy in the paramagnetic tetragonal phase of BaFe 2 As 2." Physical Review B, 96 (2017) : 20404.Unknown


    Liu, ZH; Yaresko, AN; Li, Y; Dai, PC; Zhang, H; B真chner, B; Lin, CT; Borisenko, SV; "Observation of the weak electronic correlations in KFeCoAs2 (3d 6): an isoelectronic to the parent compounds of 122 series of iron pnictides BaFe2As2." Journal of Physics: Condensed Matter, 29 (2017) : 85503.Unknown


    Man, Haoran; Guo, Jiangang; Zhang, Rui; Schonemann, Rico U; Yin, Zhiping; Fu, Mingxuan; Stone, Matthew B; Huang, Qingzhen; Song, Yu; Wang, Weiyi; "Spin excitations and the Fermi surface of superconducting FeS." NPJ Quantum Materials, 2 (2017) : 14.Unknown


    Man, Haoran; Shi, Zhong; Xu, Guangyong; Xu, Yadong; Chen, Xi; Sullivan, Sean; Zhou, Jianshi; Xia, Ke; Shi, Jing; Dai, Pengcheng; "Direct observation of magnon-phonon coupling in yttrium iron garnet." Physical Review B, 96 (2017) : 100406.Unknown


    Pelliciari, Jonathan; Huang, Yaobo; Ishii, Kenji; Zhang, Chenglin; Dai, Pengcheng; Chen, Gen Fu; Xing, Lingyi; Wang, Xiancheng; Jin, Changqing; Ding, Hong; "Magnetic moment evolution and spin freezing in doped BaFe 2 As 2." Scientific reports, 7 (2017) : 8003.Unknown


    Ren, MQ; Yan, YJ; Jiang, J; Tan, SY; Miao, J; Chen, C; Song, Y; Zhang, CL; Dai, PC; Xie, BP; "Lattice distortion and charge density wave in Na2Ti2Sb2O revealed by scanning tunnelling microscopy." Philosophical Magazine, 97 (2017) : 527-534.Unknown


    Song, Yu; Wang, Weiyi; Zhang, Chenglin; Gu, Yanhong; Lu, Xingye; Tan, Guotai; Su, Yixi; Bourdarot, Fr真d真ric; Christianson, AD; Li, Shiliang; "Temperature and polarization dependence of low-energy magnetic fluctuations in nearly optimally doped NaFe 0.9785 Co 0.0215 As." Physical Review B, 96 (2017) : 184512.Unknown


    Tam, David W; Song, Yu; Man, Haoran; Cheung, Sky C; Yin, Zhiping; Lu, Xingye; Wang, Weiyi; Frandsen, Benjamin A; Liu, Lian; Gong, Zizhou; "Uniaxial pressure effect on the magnetic ordered moment and transition temperatures in BaFe 2? x T x As 2 (T= Co, Ni)." Physical Review B, 95 (2017) : 60505.Unknown


    Tan, Guotai; Song, Yu; Zhang, Rui; Lin, Lifang; Xu, Zhuang; Tian, Long; Chi, Songxue; Graves-Brook, MK; Li, Shiliang; Dai, Pengcheng; "Phase diagram and neutron spin resonance of superconducting NaFe 1? x Cu x As." Physical Review B, 95 (2017) : 54501.Unknown


    Wang, Weiyi; Park, JT; Yu, Rong; Li, Yu; Song, Yu; Zhang, Zongyuan; Ivanov, Alexandre; Kulda, Jiri; Dai, Pengcheng; "Orbital selective neutron spin resonance in underdoped superconducting NaFe 0.985 Co 0.015 As." Physical Review B, 95 (2017) : 94519.Unknown


    Wang, Weiyi; Song, Yu; Hu, Ding; Li, Yu; Zhang, Rui; Harriger, LW; Tian, Wei; Cao, Huibo; Dai, Pengcheng; "Local breaking of fourfold rotational symmetry by short-range magnetic order in heavily overdoped Ba (Fe 1? x Cu x) 2 As 2." Physical Review B, 96 (2017) : 161106.Unknown


    Wu, S-F; Richard, P; Ding, H; Wen, H-H; Tan, Guotai; Wang, Meng; Zhang, Chenglin; Dai, Pengcheng; Blumberg, G; "Superconductivity and electronic fluctuations in Ba 1? x K x Fe 2 As 2 studied by Raman scattering." Physical Review B, 95 (2017) : 85125.Unknown

     Invited Papers

    "The PI has give more than 20 invited talks at international meetings over the past two years .  Details available upon request.."

     Invited Talks

    "The PI has given more than 10 invited talks in 2015.  Including APS March meeting invited talk, Golden Conference for superconductivity invited talk in Hong Kong, and internation conference for superconductivity invited talk in Geneva.."

    Editorial Positions
     Member of the Editorial Board, Journal of Physics: Condensed Matter. IOP. (2015 - 2017)

     Member of the Editorial Board, Journal of Physics: Condensed Matter. IOP Science. (2013 - 2013)

     Member of the Editorial Board, Journal of Physics: Condensed Matter. IOP. (2015 - 2015)

    Supervised Theses & Dissertations
     Hye Jung Kang, Ph. D Neutron scattering studies of electron-doped copper oxide superconductors. (2005) (Thesis Director)

     Stephen D Wilson, Ph. D Neutron Scattering Studies of heavy Fermion and copper oxide superconductors. (2007) (Thesis Director)

     Songxue Chi, Ph. D Neutron Scattering Studies of colossal magnetoresistance manganites and iron-based superconductors. (2008) (Thesis Director)

     Jun Zhao, Ph. D Spin excitations in iron-based superconductors. (2010) (Thesis Director)

     Leland W. Harriger, Ph. D Spin Excitations in iron-based superconductors. (2012) (Thesis Director)

     Meng Wang, Ph. D Magnetism in iron-based superconductors. (2013) (Thesis Director)

     Miaoyin Wang, Ph. D Spin dynamics in iron-based superconductors. (2013) (Thesis Director)

     Mengshu Liu, Ph. D Spin excitations in electron-doped copper oxide and iron pnictide superconductors. (2014) (Thesis Director)

     Scott Carr, Ph. D Spin dynamics in correlated electron materials. (2016) (Thesis Director)

     Yu Song, Ph. D Neutron scattering studies of correlated electron materials. (2016) (Thesis Director)

     Yu Li, Ph. D Neutron scattering studies of iron based superconductors. (2017) (Thesis Director)

     David Tam, Ph. D A combined neutron scatteirng computer study of iron-based superconductors. (2017) (Thesis Director)

     Weiyi Wang, Ph. D Neutron scattering studies of correllated electron materials. (2018) (Thesis Director)

     Haoran Man, Ph. D Neutron studies of correlated electron materials. (2018) (Thesis Director)

     Xingye Lu, Ph. D spin dynamics in iron pnictides. (Thesis Director)

    Awards, Prizes, & Fellowships
     Fellow, NSSA, Neutron Scattering Society of America (July 2016)

     NSSA sustained research prize, Neutron Scattering Society of America (NSSA) (July 2016)

     Highly Cited Researcher 2014, Thomson Reuter's (june 2014)

     Fellow, AAAS (Dec 2012)

     Fellow, American Physical Society (2008)

    Positions Held
     Professor of Physics, Department of Physics and Astronomy, Rice University. (2013 - 2013)

     Professor of Physics and JIAM Chair of Excellence, Department of Physics and Astronomy, The University of Tennessee-Knoxville. (2008 - 2013)

     Staff Scientist, Solid State Division, Oak Ridge National Laboratory. (1996 - 2001)

     Visiting Professor, Institute of Physics, Chinese Academy of Sciences, Beijing, China. (2014 - 2015)

     Professor of Physics, Department of Physics and Astronomy, The University of Tennessee-Knoxville. (2006 - 2008)

     Postdoc Associate, Solid State Division, Oak Ridge National Laboratory. (1993 - 1996)

     Associate Professor of Physics, Department of Physics and Astronomy, The University of Tennessee-Knoxville. (2001 - 2016)