物理学分野における放射光結晶学電子自由度秩序の観測

―共鳴X線散乱で探る静的・動的構造―

抄録

In strongly correlated electron systems, it has been known that three degrees of freedom of electrons, that is, charge, spin and orbital play very important roles in their electronic and magnetic properties. In this report we show the resonant X-ray scattering is a very powerful tool to observe charge, spin, and orbital orderings. Synchrotron X-ray diffraction experiments in high pressure and magnetic field are introduced to reveal the mechanism of the orderings. It is also reported that the orbital excitation is studied by resonant inelastic X-ray scattering.