Prof. Atsushi Fujimori (Department of Physics, University of Tokyo, Japan)

Title: Photoemission studies of high-temperature superconductors under mechanical strain

Time: 16:15-17:15, Fri., Oct. 12, 2018

Place: Meeting Room 410, HPSTAR (Shanghai)

Host: Toshimori Sekine

Abstract：

In the phase diagrams of high-temperature superconductors, various phases of known and un-known origins emerge and compete/cooperate with superconductivity as one varies carrier densi-ty, temperature, pressure, etc. The elucidation of the competing/cooperating phases is believed to provide key information about the superconductivity mechanism. Photoemission spectroscopy is a powerful tool to study the electronic structure of solids, but ultrahigh-vacuum conditions nec-essary for this technique have precluded the studies of materials under pressure. Recently, it has become possible to perform photoemission experiment on samples under epitaxial strain, and more recently on samples under mechanically applied uniaxial strain. In this talk, I will present recent photoemission results on iron-based superconductors and cuprate superconductors in the mysterious “pseudogap” phases, where “nematic” instability (four-fold rotational symmetry breaking) has been reported recently.

Personal biography:

Professor Atsushi Fujimori is working at the Department of Physics, the University of Tokyo. He received his B.S. (1076), M.S. (1978), and D.Sc. degrees (1981) from the University of Tokyo. He was a research scientist at National Institute for Research in Inorganic Materials, Tsukuba, Japan, between 1978-1988, was appointed an associate professor at the University of Tokyo in 1988, and a professor in 1999. His has been studying the electronic structure of correlated elec-tron systems, including transition-metal compounds, high-temperature superconductors, and spintronics materials by spectroscopic methods using synchrotron.