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arXiv · 1505.06474

Enhanced Seebeck effect in graphene devices by strain and doping engineering

Mai Chung Nguyen·Viet Hung Nguyen·Huy-Viet Nguyen·Jerome Saint-Martin·Philippe Dollfus
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Abstract

In this work, we investigate the possibility of enhancing the thermoelectric power (Seebeck coefficient) in graphene devices by strain and doping engineering. While a local strain can result in the misalignment of Dirac cones of different graphene sections in the k-space, doping engineering leads to their displacement in energy. By combining these two effects, we demonstrate that a conduction gap as large as a few hundreds meV can be achieved and hence the enhanced Seebeck coefficient can reach a value higher than 1.4 mV/K in graphene doped heterojunctions with a locally strained area. Such hetero-channels appear to be very promising for enlarging the applications of graphene devices as in strain and thermal sensors.

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Mai Chung Nguyen, Viet Hung Nguyen, Huy-Viet Nguyen, Jerome Saint-Martin, Philippe Dollfus. 2015-06-22. Enhanced Seebeck effect in graphene devices by strain and doping engineering. https://doi.org/10.1016/j.physe.2015.05.020

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