Local Hall effect in hybrid ferromagnetic/semiconductor devices

TL;DR

This paper explores the local Hall effect in hybrid ferromagnetic/semiconductor devices with sinusoidal magnetic fields, revealing large magnetoresistance and negative resistance at low temperatures, with potential spintronic applications.

Contribution

It demonstrates the existence of a local Hall effect in ferromagnet-semiconductor devices with sinusoidal magnetic profiles, supported by numerical analysis.

Findings

Large magnetoresistance observed in the device

Additional odd contribution to longitudinal resistance

Negative resistance at low temperatures in ballistic transport regime

Abstract

We have investigated the magnetoresistance of ferromagnet-semiconductor devices in an InAs two-dimensional electron gas system in which the magnetic field has a sinusoidal profile. The magnetoresistance of our device is large. The longitudinal resistance has an additional contribution which is odd in applied magnetic field. It becomes even negative at low temperature where the transport is ballistic. Based on the numerical analysis, we confirmed that our data can be explained in terms of the local Hall effect due to the profile of negative and positive field regions. This device may be useful for future spintronic applications.