Localisation and interaction effects in metallic n-type InP

Abstract

We present results on the magnetic field induced metal–insulator transition (MIT) in compensated InP. The experiments were carried out at low temperatures in the range 4.2–0.066 K and in magnetic fields up to 11 T. Not too close to the MIT the electrical conductivity σ was found to obey σ= σ( T=0)+ mT 1/2 where both the inelastic diffusion length L I∼( σ( T=0)) 3/2/ T 1/2 and the interaction length L T∼( σ( T=0)) 1/2/ T 1/2 contribute to a T 1/2 term in σ. It is convenient to develop a criterion to distinguish their contribution. It is based on the relation between the magnitude m and the zero temperature conductivity σ( T=0).