[12p-A501-1~16] 10.4 半導体スピントロニクス・超伝導・強相関

▼ [12p-A501-1] Fe concentration dependence of the Fe 3d electronic states in p-type ferromagnetic semiconductor (Ga_1-x,Fe_x)Sb

〇Takahito Takeda¹、Kohsei Araki¹、Yuita Fujisawa²、Le Duc Anh^1,3、Nguyen Thanh Tu^1,4、Tukiharu Takeda⁵、Shin-ichi Fujimori⁵、Atsushi Fujimori^6,7、Masaaki Tanaka^1,8、Masaki Kobayashi^1,8 (1.EEIS, Univ. of Tokyo、2.QMSU, OIST、3.IEI, Univ. of Tokyo、4.Dep. of Phys., Ho Chi Minh City Univ. of Pedagogy、5.JAEA、6.Dep. of Phys., Univ. of Tokyo、7.Dep. of Appl. Phys., Waseda Univer.、8.CSRN, Univ. of Tokyo)

キーワード：ferromagnetic semiconductor, 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 temperatures (T_C) of III-V based FMSs were much lower than room temperature (RT) despite tremendous efforts for the past several decades. Recently, Tu et al., have successfully grown p-type (Ga_1-x,Fe_x)Sb whose T_C is higher than RT. Magnetic circular dichroism (MCD), magnetotransport, and magnetization measurements indicate that (Ga_1-x,Fe_x)Sb is an intrinsic ferromagnetic semiconductor. sing angle-resolved photoemission spectroscopy (ARPES), we found that the ferromagnetism in (Ga_1-x,Fe_x)Sb originates from double-exchange interaction. In this study, we have conducted resonant photoemission spectroscopy (RPES) measurements at the Fe L₃ absorption edge on (Ga_1-x,Fe_x)Sb thin films with x = 0.05, 0.15, and 0.25 to reveal the Fe concentration dependence of the Fe 3d states.