报告信息
报告题目：Novel superconductivity and normal state behavior in Kagome metals and overdoped cuprate with strange metal behavior
摘要：
We demonstrate that soft fluctuations of translation symmetry-breaking loop currents provide a mechanism for unconventional superconductivity in kagome metals that naturally addresses the multiple superconducting phases observed under pressure. We show that loop currents involving both vanadium and antimony orbitals generate low-energy collective modes that couple efficiently to electrons near the Fermi surface and mediate attractive interactions in two distinct unconventional pairing channels. While loop-current fluctuations confined to vanadium orbitals favor chiral superconductivity, which spontaneously breaks time-reversal symmetry. We also study a model of mesoscale superconducting puddles in a metal, represented as dynamical impurities interacting with a finite number of electronic channels via Andreev and normal scattering. We identify conditions under which the collection of puddles make a T-linear contribution to the resistivity and TLog(T) contributions to the specific heat and thermopower. The phenomenology of our theory resembles the apparent extended strange metal regime observed in overdoped cuprates which exhibits T-linear resistivity at low temperatures over a finite range of doping. We also propose to engineer a strange metal from suitably designed superconducting grains in a metallic matrix.
简 历：
Jörg Schmalian received his doctoral degree in 1993 at the Freie University in Berlin. He has contributed more than 230 scholarly articles to the peer reviewed literature and given more than 350 invited talks at international conferences. At the Karlsruhe Institute of Technology (KIT) he is the head of the Institute for Theory of Condensed Matter (TKM). His research group at TKM works on strongly correlated electron systems and complex quantum matter. He also heads the division Theory of Quantum Materials at the Institute for Quantum Materials and Technologies (IQMT) at KIT. Prior to moving to Karlsruhe in 2011, Dr. Schmalian was a full professor at Iowa State University and Senior Scientists at the Department of Energy Ames Laboratory. Schmalian serves on a number of international advisory boards, has co-organized numerous international conferences, workshops and summer schools, and has been honored by several awards, including a fellowship from the American Physical Society, the 2022 John Bardeen Prize for superconductivity theory, the 2023 Physics-Award Dresden, and teaching awards at Iowa State Univ. and KIT. He is a member of the Heidelberg Academy of Sciences.