Eur. Phys. J. B (2013) 86: 210
https://doi.org/10.1140/epjb/e2013-40122-4

Regular Article

Adiabatic quantum pumping in graphene with magnetic barriers

National Research Center “Kurchatov Institute”, Kurchatov Sq. 1, 123182 Moscow, Russia

^a e-mail: evgeny.sg@gmail.com

Received: 13 February 2013
Received in final form: 20 March 2013
Published online: 7 May 2013

Abstract

We study an adiabatic quantum pump effect in a two terminal graphene device with two oscillating square electric barriers and a stationary magnetic barrier using the scattering matrix approach. The model employs the low-energy Dirac approximation and incorporates the possible existence of a finite band gap in graphene spectrum. We show that in this case valley-polarized and pure valley currents can be pumped due to the valley symmetry breaking. For a δ-function magnetic barrier we present analytical expressions for bilinear total and valley pumping responses. These results are compared to numerical ones for a double δ-function, a square and a triple square magnetic barriers.