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arXiv · 0907.3173

Photo-Thermoelectric Effect at a Graphene Interface Junction

Xiaodong Xu·Nathaniel M. Gabor·Jonathan S. Alden·Arend van der Zande·Paul L. McEuen
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Abstract

We investigate the optoelectronic response of a graphene interface junction, formed with bilayer and single-layer graphene, by photocurrent (PC) microscopy. We measure the polarity and amplitude of the PC while varying the Fermi level by tuning a gate voltage. These measurements show that the generation of PC is by a photo-thermoelectric effect. The PC displays a factor of ~10 increase at the cryogenic temperature as compared to room temperature. Assuming the thermoelectric power has a linear dependence on the temperature, the inferred graphene thermal conductivity from temperature dependent measurements has a T^{1.5} dependence below ~100 K, which agrees with recent theoretical predictions.

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Xiaodong Xu, Nathaniel M. Gabor, Jonathan S. Alden, Arend van der Zande, Paul L. McEuen. 2009-07-18. Photo-Thermoelectric Effect at a Graphene Interface Junction. https://doi.org/10.1021/nl903451y

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