Observation of charge ordering state in LiV2O4 investigated by optical study

Abstract

We have been investigated the electronic states of LiV2O 4 under high pressures and low temperatures analyzed by optical study using an infrared microscope. The optical conductivities derived from reflectivities clearly exhibit the change from a metallic state at ambient pressure to an insulating state at 13 GPa with the pseudo gap of Δ ∼ 0.5 eV at the low temperature of 40 K. The Drude response observed at ambient pressure declines at high pressures even at 300 K. A softening phenomenon of a residual ray band structure is verified through the temperature change from 300 K to 40 K at 13 GPa. © 2009 IOP Publishing Ltd.