Gate driven adiabatic quantum pumping in graphene

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 is not quantized.

► We propose a new type of quantum pump made out of graphene. ► The system is adiabatically driven by oscillating voltages applied to two back gates. ► Graphene pumps can tap into evanescent modes as a consequence of chirality. ► The pumping response is universal at the Dirac point for wide and short pumps. ► Graphene-based quantum pumps are more efficient than comparable normal pumps.