B. L. Gallagher

Mn Interstitial Diffusion in (Ga, Mn)As

We present a combined theoretical and experimental study of the ferromagnetic semiconductor (Ga,Mn)As which explains the remarkably large changes observed on low-temperature annealing. Careful control of the annealing conditions allows us to obtain samples with ferromagnetic transition temperatures up to 159 K. Ab initio calculations, in situ Auger spectroscopy, and resistivity measurements during annealing show that the observed changes are due to out diffusion of Mn interstitials towards the surface, governed by an energy barrier of 0.7-0.8 eV. Electric fields induced by Mn acceptors have a significant effect on the diffusion.

Prospects for high temperature ferromagnetism in (Ga,Mn)As semiconductors

We report on a comprehensive combined experimental and theoretical study of Curie temperature trends in (Ga,Mn)As ferromagnetic semiconductors. Broad agreement between theoretical expectations and measured data allows us to conclude that

High-Curie-temperature Ga1−xMnxAs obtained by resistance-monitored annealing

{T}_{c}

Electrical switching of an antiferromagnet

in high-quality metallic samples increases linearly with the number of uncompensated local moments on

Magnetoresistance of a two-dimensional electron gas due to a single magnetic barrier and its use for nanomagnetometry

{\mathrm{Mn}}_{\mathrm{Ga}}

Achieving high Curie temperature in (Ga,Mn)As

acceptors, with no sign of saturation. Room temperature ferromagnetism is expected for a 10% concentration of these local moments. Our magnetotransport and magnetization data are consistent with the picture in which Mn impurities incorporated during growth at interstitial

An antidamping spin–orbit torque originating from the Berry curvature

{\mathrm{Mn}}_{\mathrm{I}}

Spin Reorientation Transition in Single-Domain (Ga, Mn)As

positions act as double-donors and compensate neighboring

Character of states near the Fermi level in (Ga,Mn)as : Impurity to valence band crossover

{\mathrm{Mn}}_{\mathrm{Ga}}

Curie point singularity in the temperature derivative of resistivity in (Ga,Mn)As.

local moments because of strong near-neighbor