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arXiv · 1012.0658

Enhanced thermopower under time-dependent gate voltage

Adeline Crépieux·Fedor Simkovic·Benjamin Cambon·Fabienne Michelini
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Abstract

We derive formal expressions of time-dependent energy and heat currents through a nanoscopic device using the Keldysh nonequilibrium Green function technique. Numerical results are reported for a metal/dot/metal junction where the dot level energy is abruptly changed by a step-shaped voltage pulse. Analytical linear responses are obtained for the time-dependent thermoelectric coefficients. We show that the Seebeck coefficient can be enhanced in the transient regime up to an amount (here rising 40%) controlled by both the dot energy and the height of the voltage step.

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Adeline Crépieux, Fedor Simkovic, Benjamin Cambon, Fabienne Michelini. 2010-12-03. Enhanced thermopower under time-dependent gate voltage. https://doi.org/10.1103/physrevb.83.153417

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