[12p-S302-1~17] 10.4 半導体スピントロニクス・超伝導・強相関

▼ [12p-S302-14] Onset of ferromagnetism in Fe-doped magnetic semiconductors depending on the electron occupation of the impurity band

〇Takahito Takeda¹、Shoya Sakamoto²、Le Duc Anh^1,3,4、Yukiharu Takeda⁵、Shin-ichi Fujimori⁵、Miho Kitamura⁶、Koji Horiba⁶、Hiroshi Kumigashira^6,7、Atsushi Fujimori^8,9、Masaaki Tanaka^1,10、Masaki Kobayashi^1,10 (1.Grad. Sch. Eng., Univ. of Tokyo、2.ISSP, Univ. of Tokyo、3.IEI, Univ. of Tokyo、4.PRESTO, JST、5.MSRC, JAEA、6.IMSS, KEK、7.IMRAM, Tohoku Univ.、8.Dep. Phys., Univ. of Tokyo、9.Dep. Appl. Phys., Waseda Univ.、10.CSRN, Univ. of Tokyo)

キーワード：resonant photoemission spectroscopy, x-ray magnetic circular dichroism, ferromagnetic semiconductor

Ferromagnetic semiconductors (FMSs) are realized by introducing magnetic ions in semiconductor hosts. The magnetic interaction between the doped magnetic ions is mediated by the spin of the carriers, and such ferromagnetism is called carrier-induced ferromagnetism. Recently, to unveil the origin of the ferromagnetism of the Fe-doped III-V FMSs, the electronic structures and magnetic properties of the Fe-doped III-V FMSs have been studied by soft x-ray spectroscopy. In this study, we have focused on the paramagnetic Fe-doped III-V semiconductor (Ga,Fe)As. The comparison of the experimental results between paramagnetic (Ga,Fe)As and other Fe-doped III-V FMSs is helpful for unveiling the mechanism of the ferromagnetism. Based on the observations, we have found that the occupancy of the e_↓ states contributes to the appearance of the ferromagnetism in the Fe-doped III-V semiconductors, for p-type as well as n-type.