Temperature Dependence of the Optical Response of Perovskite-type SrIrO3 Thin Film

Abstract

We report on the temperature-dependent optical absorption spectra of an orthorhombic SrIrO3 thin film in the energy region between 0.08 and 6 eV. The optical absorption spectra show the characteristic spectral features associated with spin-orbit coupling-induced effective total angular momentum J(eff) states. A Drude-like response from the electrons in the J(eff) = 1/2 bands is observed in the energy region below about 0.5 eV followed by an interband transition from the J(eff) = 3/2 to the J(eff) = 1/2 bands at 0.7 eV. The electron excitations between the J(eff) bands exhibit a strong temperature dependence that is different from the behavior of conventional metals. The spectral weight analysis of the absorption data suggests an anomalous low-frequency electrodynamic behavior for of SrIrO3.