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arXiv · 1105.3282

Enhanced Thermoelectric Power in Dual-Gated Bilayer Graphene

Chang-Ran Wang·Wen-Sen Lu·Lei Hao·Wei-Li Lee·Ting-Kuo Lee·Feng Lin·I-Chun Cheng·Jian-Zhang Chen
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Abstract

Thermoelectric power of a material, typically governed by its band structure and carrier density, can be varied by chemical doping that is often restricted by solubility of the dopant. Materials showing large thermoelectric power are useful for many industrial applications, such as the heat-to-electricity conversion and the thermoelectric cooling device. Here we show a full electric field tuning of thermoelectric power in a dual-gated bilayer graphene device resulting from the opening of a band-gap by applying a perpendicular electric field on bilayer graphene. We uncover a large enhancement in thermoelectric power at low temperature, which may open up a new possibility in low temperature thermoelectric application using graphene-based device.

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Chang-Ran Wang, Wen-Sen Lu, Lei Hao, Wei-Li Lee, Ting-Kuo Lee, Feng Lin, I-Chun Cheng, Jian-Zhang Chen. 2011-05-17. Enhanced Thermoelectric Power in Dual-Gated Bilayer Graphene. https://doi.org/10.1103/physrevlett.107.186602

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