Nature of Magnetism in III-V based Diluted Magnetic Semiconductors
S. Katsumoto, T. Hayashi, Y. Hashimoto, Y. Iye, Y. Ishiwata, M. Watanabe, R. Eguchi, T. Takeuchi, Y. Harada,
Note: NGS10 Proceedings
A systematic study on magnetism and transport in III-V based diluted magnetic semiconductors (Ga,Mn)As and (In,Mn)As is presented. Low-temperature annealing effect is utilized to control material parameters. X-ray absorption spectroscopy revealed that Mn-ions that contribute to the ferromagnetism are in d5 states, hence the holes should mainly be in As 4p states. On the other hand, infrared optical conductivity measurements indicate those holes are almost localized. These results naturally provide a picture for the ferromagnetism in these materials. The low-temperature annealing is also applied to detailed study of the metal-insulator transi-tion.