149Sm nuclear resonant inelastic scattering of SmB6

Abstract

149Sm nuclear resonant inelastic scattering was carried out in SmB6 in order to investigate the lattice dynamics due to Sm atoms. A sharp phonon excitation associated with Sm atoms is observed around 10 meV, suggesting the presence of a Sm dispersionless mode. The Sm phonon energy shows significant temperature dependence, correlated with temperature dependence of Sm valence state. The nuclear resonant inelastic scattering spectra also indicate that the electronic configuration at the Sm site is 4f5 hybridized with the conduction electrons. © 2009 IOP Publishing Ltd.