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arXiv · 1304.2526

Pudding-mold type band in a potential thermoelectric material CuAlO$_2$ : comparison with Na$_x$CoO$_2$

Kouta Mori·Hirofumi Sakakibara·Hidetomo Usui·Kazuhiko Kuroki
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Abstract

A potential thermoelectric material CuAlO$_2$ is theoretically studied. We first construct a model Hamiltonian of CuAlO$_2$ based on the first principles band calculation, and calculate the Seebeck coefficient. Then, we compare the model with that of a well-known thermoelectric material Na$_x$CoO$_2$, and discuss the similarities and the differences. It is found that the two materials are similar from an electronic structure viewpoint in that they have a peculiar pudding-mold type band shape, which is advantageous as thermoelectric materials. There are however some differences, and we analyze the origin of the difference from a microscopic viewpoint. The band shape of CuAlO$_2$ is found to be even more ideal than that of Na$_x$CoO$_2$, and we predict that once a significant amount of holes is doped in CuAlO$_2$, thermoelectric properties (especially the power factor) even better than that of Na$_x$CoO$_2$ can be expected.

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Kouta Mori, Hirofumi Sakakibara, Hidetomo Usui, Kazuhiko Kuroki. 2013-04-09. Pudding-mold type band in a potential thermoelectric material CuAlO$_2$ : comparison with Na$_x$CoO$_2$. https://doi.org/10.1103/physrevb.88.075141

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