报告题目：Normal and superconducting states of cuprates: an emergent Bose liquid?
Besides the puzzling high-temperature superconductivity, cuprates also features numerous unusual normal-state properties. This talk will present a simple picture of an emergent Bose liquid (EBL) and demonstrate several non-Fermi liquid characteristics of EBL that seems to capture the essence of the normal and superconducting states of cuprates. These include: 1) bad metal behavior (linear resistivity beyond the Mott limit), 2) mid-infrared features in optical conductivity, 3) non-Fermi liquid scattering rate, 4) zero-temperature phase diagram, 5) diminishing superfluid stiffness at high doping, and 6) weak doping dependence of superconducting gap. The similarities in these highly unusual characteristics suggest strongly that cuprates are a prototype of EBL, and EBL might often take place in strongly correlated materials that complements the standard textbook Fermi liquid in condensed matter systems.
After receiving his PhD degree from University of Tennessee at Knoxville in 2000, professor Wei Ku conducted his postdoctoral research in University of California at Davis from 2001 to 2003. He then worked as a staff scientist (Assistant Physicist, Associate Physicist, and Physicist) in Brookhaven National Laboratory and served as an Adjunct Professor in Stony Brook University since 2003, until he accepted the Zhiyuan Professor position in Shanghai Jiao Tong University in 2016. In 2018, professor Wei Ku was appointed Deputy Director of the newly found Tsung-Dao Lee Institute in Shanghai, assisting Founding Director Frank Wilczek, the 2004 Nobel Laureate in Physics. His main research area is theory and computation of condensed matter physics in real materials, with contributions mostly in the field of Fe-based high-temperature superconductors, electronic excitations, and first-principles computational methods. He has published more than 80 manuscripts, about half of which are in high-profile journals like the PNAS, Nature Physics, Phys. Rev. X, and Phys. Rev. Lett. He is currently developing an “emergent Bose liquid” theory for strongly correlated condensed matter systems, and applying it to the description of electronic structure of high-temperature superconducting cuprates.