Reflectance and resistivity of barely metallic LaTiO3

The absolute reflectance of LaTiO3 was measured from 70 to 17 500 cm-1. The Kramers-Kronig-derived optical conductivity shows three sharp phonon structures near 170, 340, and 540 cm-1 that are explained by a factor-group analysis. The midinfrared spectrum is dominated by a broad absorption band with an onset near 600 cm-1. A comparison of reflectance and resistivity measurements indicates that the dc mobility is less than 3 cm2/V s at 300 K, and thus the carriers are somewhat localized.