Photo-thermoelectric effect at a graphene interface junction

Nano Lett. 2010 Feb 10;10(2):562-6. doi: 10.1021/nl903451y.

Abstract

We investigate the optoelectronic response of a graphene single-bilayer interface junction using 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 photothermoelectric effect. The PC displays a factor of approximately 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 approximately 100 K, which agrees with recent theoretical predictions.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.