First-principles calculations for high-temperature ferromagnetic semiconductor (In,Fe)Sb*

Fe-doped semiconductors have been attracting much attention due to fascinating properties. In fact, Fe-doped InSb not only exhibits the high Curie temperature but can also be n-type doping [1]. Our previours calculations reveal that, (In,Fe)Sb has complex magnetic properties [2]. In the isoelectronic (In,Fe)Sb case, the Fe atoms show strong antiferromagnetic interactions due to the superexchange mechanism. We have demonstrated that by modulating the chemical potentials corresponding to n- or p-type doping, the magnetic property can be changed drastically from antiferromagnetism to ferromagnetism. This transition can be well understood in terms of the Alexander-Anderson-Moriya mechanism. However, we have obtained high Curie temperature in only p-type (In,Fe)Sb case. We suspect that there are the other ferromagnetic mechanisms in addition to the magnetic transition and spinodal nano-decomposition in (In,Fe)Sb. In this study, we have clarified the origin of high Curie temperature by the density functional theory calculations.

[1] N. T. Tu, et al., Appl. Phys. Lett. 108, 192401 (2016).
[2] H. Shinya, et al., J. Appl. Phys. 124, 103902 (2018).