Heavily Fe-doped n-type ferromagnetic semiconductor (In,Fe)Sb with high Curie temperature and large magnetic anisotropy

TL;DR

This paper reports the synthesis of heavily Fe-doped (In,Fe)Sb thin films exhibiting high Curie temperature, large magnetic anisotropy, and potential for room-temperature spintronics applications.

Contribution

It demonstrates the highest Curie temperature in III-V ferromagnetic semiconductors and maintains zinc-blende structure with single-phase ferromagnetism at high Fe doping levels.

Findings

Curie temperature reaches 390 K at 35% Fe doping

Large coercive force of 160 Oe observed

High remanent magnetization of 71%

Abstract

We present high-temperature ferromagnetism and large magnetic anisotropy in heavily Fe-doped n-type ferromagnetic semiconductor (In1-x,Fex)Sb (x = 20 - 35%) thin films grown by low-temperature molecular beam epitaxy. The (In1-x,Fex)Sb thin films with x = 20 - 35% maintain the zinc-blende crystal and band structure with single-phase ferromagnetism. The Curie temperature (TC) of (In1-x,Fex)Sb reaches 390 K at x = 35%, which is significantly higher than room temperature and the highest value so far reported in III-V based ferromagnetic semiconductors. Moreover, large coercive force (HC = 160 Oe) and large remanent magnetization (Mr/MS = 71%) have been observed for a (In1-x,Fex)Sb thin film with x = 35%. Our results indicate that the n-type ferromagnetic semiconductor (In1-x,Fex)Sb is very promising for spintronics devices operating at room temperature.