Weyl semimetal phase in solid-solution narrow-gap semiconductors

Daichi Kurebayashi; Kentaro Nomura

doi:10.7566/jpsj.83.063709

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arXiv · 1404.5132

Weyl semimetal phase in solid-solution narrow-gap semiconductors

Daichi Kurebayashi·Kentaro Nomura

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Abstract

We theoretically investigate ferromagnetic ordering in magnetically doped solid-solution narrow-gap semiconductors with the strong spin-orbit interaction such as Cr-doped Bi$_2$(Se$_x$Te$_{1-x}$)$_3$. We compute the spontaneous magnetization of impurities and itinerant electrons, and estimate the critical temperature as a function of the concentration of magnetic dopants and the strength of the spin-orbit interaction. It is found that the critical temperature is proportional to the concentration of dopants and enhanced with the strong spin-orbit interaction. It is also found that the ferromagnetic transition could make the system turn to the Weyl semimetal which possesses a pair of Weyl points separating in the momentum space.

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Daichi Kurebayashi, Kentaro Nomura. 2014-04-21. Weyl semimetal phase in solid-solution narrow-gap semiconductors. https://doi.org/10.7566/jpsj.83.063709

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