报告时间：2023年5月8日 10:00-12:00
报告地点：江湾校区一号交叉楼A5005
摘要：Accurate and practical ab initio treatment of electron-phonon (e-ph) coupling is essential to the understanding of many condensed-matter phenomena. In this talk, I will present a new ab initio linear-response method named GW perturbation theory (GWPT) that computes the e-ph interaction with the inclusion of the GW nonlocal, energy-dependent self-energy effects [1]. GWPT goes beyond the commonly used density-functional perturbation theory (DFPT), which is inadequate in some materials where correlation effects are non-negligible. We first demonstrate the capability of GWPT by showing that the e-ph coupling in Ba1-xKxBiO3 is significantly enhanced by many-electron correlations, strong enough to explain its high superconducting Tc of 32 K [1]. Secondly, using full GW-level anisotropic Eliashberg equation calculations, we predict that the recently discovered infinite-layer nickelate superconductor Nd1-xSrxNiO2 hosts a strong phonon-mediate two-gap s-wave superconductivity, explaining some intriguing experimental observations [2]. Thirdly, we study the ubiquitous 70-meV dispersion kink in cuprates observed in angle-resolved photoemission experiments, and show that the correlation-enhanced e-ph interaction in La2-xSrxCuO4 gives rise to strong nodal kinks and their temperature and doping dependence in quantitative agreement with experiments [3].
参考文献：
[1] Z. Li, G. Antonius, M. Wu, F. da Jornada, and S. G. Louie, Phys. Rev. Lett. 122, 186402 (2019).
[2] Z. Li and S. G. Louie, arXiv:2210.12819 (2022).
[3] Z. Li, M. Wu, Y.-H. Chan, and S. G. Louie, Phys. Rev. Lett. 126, 146401 (2021).4. Zhang, X., Chen, H., Wang, E., Shi, J., & Li, X., Phys. Rev. B, 105, 155148 (2022)
