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Doping Dependent Changes in Nitrogen 2$p$ States in the Diluted Magnetic Semiconductor Ga$_{1-x}$Cr$_{x}$N

T. Takeuchi·Y. Harada·T. Tokushima·M. Taguchi·Y. Takata·A. Chainani·J. J. Kim·H. Makino·T. Yao·T. Yamamoto·T. Tsukamoto·S. Shin·K. Kobayashi
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Abstract

We study the electronic structure of the recently discovered diluted magnetic semiconductor Ga$_{1-x}$Cr$_{x}$N ($x$ = 0.01-0.10). A systematic study of the changes in the $occupied$ and $unoccupied$ ligand (N) partial density of states (DOS) of the host lattice is carried out using N 1$s$ soft x-ray emission and absorption spectroscopy, respectively. X-ray absorption measurements confirm the wurtzite N 2$p$ DOS and substitutional doping of Cr into Ga-sites. Coupled changes in the $occupied$ and $unoccupied$ N 2$p$ character DOS of Ga$_{1-x}$Cr$_{x}$N identify states responsible for ferromagnetism consistent with band structure calculations.

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T. Takeuchi, Y. Harada, T. Tokushima, M. Taguchi, Y. Takata, A. Chainani, J. J. Kim, H. Makino, T. Yao, T. Yamamoto, T. Tsukamoto, S. Shin, K. Kobayashi. 2004-09-30. Doping Dependent Changes in Nitrogen 2$p$ States in the Diluted Magnetic Semiconductor Ga$_{1-x}$Cr$_{x}$N. https://doi.org/10.1103/physrevb.70.245323

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