High-temperature intrinsic ferromagnetism in the (In,Fe)Sb semiconductor

TL;DR

This study demonstrates that (In,Fe)Sb layers exhibit intrinsic ferromagnetism above room temperature, confirmed by multiple techniques, with ferromagnetism likely driven by superexchange interactions rather than carriers.

Contribution

It provides evidence of high-temperature intrinsic ferromagnetism in (In,Fe)Sb, a semiconductor, with detailed structural and magnetic characterization showing superexchange as the mechanism.

Findings

Curie temperature above 300 K

Epitaxial, phase-pure (In,Fe)Sb layers

Intrinsic ferromagnetism confirmed by magnetic circular dichroism

Abstract

The (In,Fe)Sb layers with the Fe content up to 13 at. % have been grown on (001) GaAs substrates using the pulsed laser deposition. The TEM investigations show that the (In,Fe)Sb layers are epitaxial and free of the inclusions of a second phase. The observation of the hysteretic magnetoresistance curves at temperatures up to 300 K reveals that the Curie point is above room temperature. The resonant character of magnetic circular dichroism confirms the intrinsic ferromagnetism in the (In,Fe)Sb layers. We suggest that the ferromagnetism of the (In,Fe)Sb matrix is not carrier-mediated and apparently is determined by the mechanism of superexchange interaction between Fe atoms (This work was presented at the XXI Symposium Nanophysics and Nanoelectronics, Nizhny Novgorod, March, 13-16, 2017 (book of proceedings v.1, p. 195), http://nanosymp.ru/UserFiles/Symp/2017_v1.pdf).