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arXiv · 1712.08873

Possible High Thermoelectric Power in Semiconducting Carbon Nanotubes ~A Case Study of Doped One-Dimensional Semiconductors~

Takahiro Yamamoto·Hidetoshi Fukuyama
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Abstract

We have theoretically investigated the thermoelectric properties of impurity-doped one-dimensional semiconductors, focusing on nitrogen-substituted (N-substituted) carbon nanotubes (CNTs), using the Kubo formula combined with a self-consistent $t$-matrix approximation. N-substituted CNTs exhibit extremely high thermoelectric power factor ($PF$) values originating from a characteristic of one-dimensional materials where decrease in the carrier density increase both the electrical conductivity and the Seebeck coefficient in the low-N regime. The chemical potential dependence of the $PF$ values of semiconducting CNTs has also been studied as a field-effect transistor and it turns out that the $PF$ values show a noticeable maximum in the vicinity of the band edges. This result demonstrates that "band-edge engineering" will be crucial for solid development of high-performance thermoelectric materials.

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Takahiro Yamamoto, Hidetoshi Fukuyama. 2017-12-24. Possible High Thermoelectric Power in Semiconducting Carbon Nanotubes ~A Case Study of Doped One-Dimensional Semiconductors~. https://doi.org/10.7566/jpsj.87.024707

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