Quantum coherence effects and field-induced localization in InSb

Abstract

A low-temperature (0.5T4.2 K) transport study of lightly doped n-type InSb, n=5\ifmmode\times\else\texttimes\fi{}${10}^{14}$ ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}3}$, shows weak localization corrections to the resistance at low magnetic fields, B\ensuremath{\sim}30 mT, and an activated magnetoresistance in the quantum limit, i.e., magnetic freezeout. From these results, we argue that weak localization is not a precursor to the magnetic-field-induced metal-insulator transition in this narrow-gap system, since it is quenched well before the onset of magnetic freezeout.