Keywords:Ferromagnetic semiconductor, Angle-resolved photoemission spectroscopy
Ferromagnetic semiconductors (FMSs) are alloy semiconductors in which cations are partially replaced by magnetic impurities. FMSs have both the properties of ferromagnets and semiconductors and exhibit carrier-induced ferromagnetism, thereby attracting much attention as promising materials for semiconductor spintronics devices because one can control their magnetic properties by changing the carrier concentration. However, the Curie temperature (TC) of III-V based FMSs was much lower than room temperature (RT) despite tremendous efforts for the past two decades. Recently, Tu et al., have successfully grown p-type (Ga,Fe)Sb whose TC is higher than RT. Magnetic circular dichroism (MCD), magnetotransport, and magnetization measurements indicate that (Ga,Fe)Sb is an intrinsic ferromagnetic semiconductor . In this study, we conducted soft x-ray angle-resolved photoemission spectroscopy (SX-ARPES) measurements on (Ga1-x,Fex)Sb with x = 0.05 and GaSb thin films to reveal the band structure and to unveil the origin for the high-TC ferromagnetism above RT.