Negative giant longitudinal magnetoresistance in NiMnSb InSb: Interface effect

Abstract

We report on the electrical and magnetotransport properties of the contact formed between n -type degenerate InSb (100) substrates and polycrystalline NiMnSb thin films grown using pulsed laser deposition. Negative giant magnetoresistance is observed when the external magnetic field is oriented parallel to the in-plane current direction. We attribute the observed phenomenon to magnetic precipitates that are formed during the magnetic film deposition and are confined to a thin layer at the interface. The evidence for the formation of a thin interfacial layer is obtained through x-ray reflectivity measurements. © 2006 The American Physical Society.