Local electronic structure of Cr in the II-VI diluted ferromagnetic semiconductor ZnCrTe

強磁性希薄磁性半導体ZnCrTeの軟X線磁気円二色性による研究

小林 正起*; 石田 行章*; Hwang, J. I.*; Song, G. S.*; 藤森 淳; Yang, C. S.*; Lee, L.*; Lin, H.-J.*; Huang, D.-J.*; Chen, C. T.*; 竹田 幸治   ; 寺井 恒太*; 藤森 伸一   ; 岡根 哲夫  ; 斎藤 祐児  ; 山上 浩志; 小林 啓介*; 田中 新*; 齋藤 秀和*; 安藤 功兒*

Kobayashi, Masaki*; Ishida, Yukiaki*; Hwang, J. I.*; Song, G. S.*; Fujimori, Atsushi; Yang, C. S.*; Lee, L.*; Lin, H.-J.*; Huang, D.-J.*; Chen, C. T.*; Takeda, Yukiharu; Terai, Kota*; Fujimori, Shinichi; Okane, Tetsuo; Saito, Yuji; Yamagami, Hiroshi; Kobayashi, Keisuke*; Tanaka, Arata*; Saito, Hidekazu*; Ando, Koji*

The electronic structure of the Cr ions in the diluted ferromagnetic semiconductor ZnCrTe (=0.03 and 0.15) thin films has been investigated using X-ray magnetic circular dichroism (XMCD) and photoemission spectroscopy (PES). The line shape of the Cr XMCD spectra is independent of , , and , indicating that the ferromagnetism is originated from the same electronic states of the Cr ion. Cluster-model analysis indicates that the ferromagnetic XMCD signal is originated from Cr ions substituted for the Zn site. The Cr partial density of states extracted using Cr resonant PES shows a broad feature near the top of the valence band, suggesting strong ,- hybridization. Based on these findings, we conclude that double exchange mechanism cannot explain the ferromagnetism in ZnCrTe.