External Control of Magnetism in Semiconductors at High Temperature (~100K)

TL;DR

This paper reports the electrical and optical control of ferromagnetism in Mn-doped GaAs heterostructures at high temperatures (~100K), enabling potential device applications.

Contribution

It introduces a method to electrically and optically modulate high-temperature ferromagnetism in semiconductor heterostructures with a transition temperature over 100 K.

Findings

Achieved ferromagnetic transition temperatures up to 172 K.

Demonstrated isothermal switching between paramagnetic and ferromagnetic states.

Observed a significant modulation of TC (~15 K) at high temperatures.

Abstract

We demonstrate the electrical and optical control of ferromagnetism in semiconductor heterostructures at high temperatures of 100-117 K. The heterostructures consist of Mn delta-doped GaAs and p-type AlGaAs, where the overlap of the hole wavefunction with the Mn delta-doping profile leads to high ferromagnetic transition temperature TC of over 100 K (max. 172 K). We are able to isothermally change the paramagnetic state to the ferromagnetic state and vice versa, by applying a gate electric-field or by light irradiation. The large modulation of TC (DTC ~15 K) at high temperatures (> ~100 K) demonstrated here may pave the way to functional device applications compatible with the present semiconductor technology.