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arXiv · 1104.2651

Bipolar thermoelectric effect in a srially coupled quantum dot system

David M. -T. Kuo·Yia-chung Chang
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Abstract

The Seebeck coefficient (S) of a serially coupled quantum dot (SCQD) junction system is theoretically studied via a two-level Anderson model. A change of sign in S with respect to temperature is found, which arises from the competition between tunneling currents due to electrons and holes (i.e, bipolar tunneling effect). The change of sign in S implies that one can vary the equilibrium temperature to produce thermoelectric current in either the forward or reverse direction, leading to a bipolar thermoelectric effect. For the case of two parallel SCQDs, we also observe the oscillatory behavior of S with respect to temperature.

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David M. -T. Kuo, Yia-chung Chang. 2011-11-01. Bipolar thermoelectric effect in a srially coupled quantum dot system. https://doi.org/10.1143/jjap.50.105003

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