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arXiv · 1103.5597

Single-parameter pumping in graphene

Pablo San-Jose·Elsa Prada·Sigmund Kohler·Henning Schomerus
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Abstract

We propose a quantum pump mechanism based on the particular properties of graphene, namely chirality and bipolarity. The underlying physics is the excitation of evanescent modes entering a potential barrier from one lead, while those from the other lead do not reach the driving region. This induces a large nonequilibrium current with electrons stemming from a broad range of energies, in contrast to the narrow resonances that govern the corresponding effect in semiconductor heterostructures. Moreover, the pump mechanism in graphene turns out to be robust, with a simple parameter dependence, which is beneficial for applications. Numerical results from a Floquet scattering formalism are complemented with analytical solutions for small to moderate driving.

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Pablo San-Jose, Elsa Prada, Sigmund Kohler, Henning Schomerus. 2011-03-29. Single-parameter pumping in graphene. https://doi.org/10.1103/physrevb.84.155408

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