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arXiv · 1007.3161

Gate driven adiabatic quantum pumping in graphene

Elsa Prada·Pablo San-Jose·Henning Schomerus
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Abstract

We propose a new type of quantum pump made out of graphene, adiabatically driven by oscillating voltages applied to two back gates. From a practical point of view, graphene-based quantum pumps present advantages as compared to normal pumps, like enhanced robustness against thermal effects and a wider adiabatic range in driving frequency. From a fundamental point of view, apart from conventional pumping through propagating modes, graphene pumps can tap into evanescent modes, which penetrate deeply into the device as a consequence of chirality. At the Dirac point the evanescent modes dominate pumping and give rise to a universal response under weak driving for short and wide pumps, even though the charge per unit cycle in not quantized.

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Elsa Prada, Pablo San-Jose, Henning Schomerus. 2011-07-15. Gate driven adiabatic quantum pumping in graphene. https://doi.org/10.1016/j.ssc.2010.12.042

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