Magnetic-field induced metal-insulator transition in SrTiO 3 − δ

Abstract

Metallic samples of SrTiO3−δ with charge-carrier densities of n = 8.6 × 1016 cm−3 and 2.0 × 1017 cm−3 are shown to exhibit magnetic-field-induced metal–insulator transitions. Landau levels emerge in the magnetic field, and their energy spacing is comparable to the Fermi and thermal energies. A simple parallel-conduction model involving thermally-activated hopping among Landau levels is introduced to describe the data below the metal–insulator transition temperature.