High Ferromagnetic Transition Temperature (172K) in Mn delta-doped GaAs with p-type Selective Doping

TL;DR

This paper reports a significant increase in ferromagnetic transition temperature up to 172K in Mn delta-doped GaAs heterostructures with p-type doping, achieved through selective doping and annealing, advancing spintronic material development.

Contribution

It demonstrates that selective p-type doping in Mn delta-doped GaAs heterostructures significantly enhances ferromagnetic transition temperature, reaching 172K, which is higher than previous results.

Findings

High ferromagnetic transition temperature (172K) achieved.

Selective doping with Be-doped AlGaAs supplies holes effectively.

Low-temperature annealing improves ferromagnetic properties.

Abstract

We have found high ferromagnetic transition temperature in Mn delta-doped GaAs-based heterostructures grown on GaAs(001) substrates by molecular beam epitaxy. A 0.3 ML Mn d-doped GaAs samples showed high resistivity at low temperature and did not show a ferromagnetic behavior. However, in a selectively doped heterostructure (Mn delta-doped GaAs / Be-doped AlGaAs), where holes were supplied from the Be-doped AlGaAs layer, clear ferromagnetic order was observed. The ferromagnetic transition temperature of the selectively doped heterostructure was as high as 172K with suitable low-temperature (LT) annealing treatment.