Frontier Research Institute for Interdisciplinary Sciences
Tohoku University

Electrons in solids are arranged on a crystal lattice and interact with each other via Coulomb interactions. The collective motion of the electrons follows the laws of quantum mechanics and is one of the most challenging problems in condensed matter physics. These strongly correlated electrons, however, often provide a fertile playground for collective emergent quantum phenomena, including superconductivity, magnetism, topological phases, and quantum spin liquids. The solid state systems hosting these exotic phases, termed as “Quantum Materials”, have enlarged their scope with the aid of advances in growing high-quality single crystals and in fabricating their functional devices.

The goal of my research is to provide microscopic insights into these emergent phenomena through the lens of advanced photon spectroscopy. I aim to develop and exploit new spectroscopic techniques at the next-generation 3GeV synchrotron facility under construction at Aobayama campus of Tohoku University. I will in particular focus on the use of resonant inelastic x-ray scattering (RIXS) technique. RIXS is a photon-in, photon-out light scattering technique in the x-ray regime, which has recently encountered a large improvement in its energy resolution. The wide applicability of RIXS and its accessibility to charge, spin, and orbital excitations allow the direct measurement of dispersion relation of elementary excitations in a large family of quantum materials. The emergent elementary excitations are often analogous to elementary particles in high-energy physics and open possibilities for future applications such as topological quantum computing. I will tackle the physics of quantum materials through a close collaboration with other members of FRIS.