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arXiv · 2001.10191

First-principles calculation of electronic density of states and Seebeck coefficient in transition-metal-doped Si-Ge alloys

Ryo Yamada·Akira Masago·Tetsuya Fukushima·Hikari Shinya·Tien Quang Nguyen·Kazunori Sato
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Abstract

High $ZT$ value and large Seebeck coefficient have been reported in the nanostructured Fe-doped Si-Ge alloys. In this work, the large Seebeck coefficient in Fe-doped Si-Ge systems is qualitatively reproduced from the computed electronic density of states, where a hybrid functional, HSE06, is used for an exchange-correlation functional, as well as a special quasi-random structure (SQS) for a disordered atomic configuration. Furthermore, by replacing Fe with other transition metals, such as Mn, Co, Ni, Cu, Zn, and Au, a better dopant that produces a larger Seebeck coefficient in Si-Ge alloy systems is explored.

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Ryo Yamada, Akira Masago, Tetsuya Fukushima, Hikari Shinya, Tien Quang Nguyen, Kazunori Sato. 2020-01-28. First-principles calculation of electronic density of states and Seebeck coefficient in transition-metal-doped Si-Ge alloys. https://doi.org/10.1016/j.ssc.2020.114115

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