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arXiv · 1604.04353

Quantum effects in the thermoelectric power factor of low-dimensional semiconductors

Nguyen T. Hung·Eddwi H. Hasdeo·Ahmad R. T. Nugraha·Mildred S. Dresselhaus·Riichiro Saito
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Abstract

We theoretically investigate the interplay between the confinement length $L$ and the thermal de Broglie wavelength $Λ$ to optimize the thermoelectric power factor of semiconducting materials. An analytical formula for the power factor is derived based on the one-band model assuming nondegenerate semiconductors to describe quantum effects on the power factor of the low dimensional semiconductors. The power factor is enhanced for one- and two-dimensional semiconductors when $L$ is smaller than $Λ$ of the semiconductors. In this case, the low-dimensional semiconductors having $L$ smaller than their $Λ$ will give a better thermoelectric performance compared to their bulk counterpart. On the other hand, when $L$ is larger than $Λ$, bulk semiconductors may give a higher power factor compared to the lower dimensional ones.

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Nguyen T. Hung, Eddwi H. Hasdeo, Ahmad R. T. Nugraha, Mildred S. Dresselhaus, Riichiro Saito. 2016-06-30. Quantum effects in the thermoelectric power factor of low-dimensional semiconductors. https://doi.org/10.1103/physrevlett.117.036602

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