Filling dependence of electronic properties on the verge of metal–Mott-insulator transition in Sr1−xLaxTiO3

Abstract

Introducing holes (or partly eliminating electrons) in Mott-Hubbard insulator ${\mathrm{LaTiO}}_3$ (with 3${\mathit{d}}^1$ configuration) can be carried out by partial substitution of La with Sr, which produces the strongly correlated metallic phase. Systematic variation of electronic properties in ${\mathrm{Sr}}_{1\mathrm{-}\mathit{x}}$ ${\mathrm{La}}_{\mathit{x}}$ ${\mathrm{TiO}}_3$ was investigated as a function of the 3d band filling (x) by measurements of resistivity, Hall coefficient, magnetic susceptibility, and specific heat. Up to the vicinity of the metal-insulator phase boundary (${\mathit{x}}_{\mathit{c}}$∼0.95), ${\mathrm{Sr}}_{1\mathrm{-}\mathit{x}}$ ${\mathrm{La}}_{\mathit{x}}$ ${\mathrm{TiO}}_3$ behaves as a Fermi liquid system where the carrier mass and scattering rate critically increase as the x=1 (${\mathrm{LaTiO}}_3$) insulator is approached.