Optical study on strongly correlated electron system LiV2O 4

Abstract

We investigate the change in the electronic states of LiV2O 4 under high pressures and low temperatures analyzed by an infrared spectromicroscopy. The optical spectra clearly exhibit the change from a metallic state under ambient pressure to an insulating state under high pressures with a newly opened gap of 2Δ ∼ 0.5 eV. The modification in the electronic band structure is featured by the appearance of a characteristic phonon. The absorption coefficient α of LiV2O4 in the pressure-induced insulating state is compared to that of AlV 2O4 in the temperature-induced one. © 2010 IOP Publishing Ltd.