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

Abstract

We present high-temperature ferromagnetism and large magnetic anisotropy in heavily Fe-doped n-type ferromagnetic semiconductor (In 1-x ,Fe x )Sb (x = 20 -35%) thin films grown by low-temperature molecular beam epitaxy. The (In 1-x ,Fe x )Sb thin films with x = 20 -35% maintain the zinc-blende crystal and band structure with single-phase ferromagnetism. The Curie temperature (T C ) of (In 1-x ,Fe x )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 (H C = 160 Oe) and large remanent magnetization (M r /M S = 71%) have been observed for a (In 1-x ,Fe x )Sb thin film with x = 35%. Our results indicate that the n-type ferromagnetic semiconductor (In 1-x ,Fe x )Sb is very promising for spintronics devices operating at room temperature.