VI-1 Electronic Degrees of Freedom and Magnetic Excitation Spectra in Rare-earth-based Metallic Systems

Abstract

f Electrons in rare-earth compounds are basically localized at rare-earth ions, and carry various degrees of freedom categorized in magnetic dipoles, electric quadrupoles, and high-rank multipoles. Because of interactions with conduction electrons, f electrons provide characteristic physical properties; Kondo effect, competition or cooperation between magnetic and charge orbital ordering, etc. Examples of inelastic neutron scattering studies on determination of quantum states of f electrons, ordering, and elementary excitations originating from many-body interctions are introduced.