Angle-resolved Photoemission Spectroscopy and its Application to Explo…

Photoemission spectroscopy is one of the powerful tools to understand electrons that ultimately determine the electronic, magnetic, chemical, mechanical, optical, thermal, and structural properties of solid materials. In this talk, I will introduce brief history of photoemission spectroscopy and several types of photoemission spectroscopy technique. More specifically, angle-resolved photoemission spectroscopy (ARPES) shows how electrons are bound within a crystal as a function of energy and momentum, revealing fundamental information ranging from basic electron band structure to complicated many-body physics. Recent development of ARPES technique made it possible to study (1) hot electrons with momentum resolution utilizing laser, so called time-resolved ARPES, and (2) another quantum number, spin, with spin-resolved ARPES. These new techniques reveal electron dynamics in ultra-fast time scale and spin information as well as intriguing spin-light interactions, respectively, which are expected to play important roles in understanding new correlated electron phases.