Landau level single-electron pumping

Abstract

We present a detailed study of the effect of a strong perpendicular magnetic field on single-electron pumping in a device utilising a finger-gate split-gate configuration, characterised by high pumping precision. In the quantum Hall regime, we demonstrate electron pumping from Landau levels in the leads, where the measurements exhibit pronounced fluctuations in the lengths of the pumping plateaus with magnetic field, reminiscent of Shubnikov–de Haas oscillations. In order to explain this similarity, we introduce a new physical model for the dynamics of the operation of a single-electron pump. We show that the pumping process is dependent on the density of states of the 2D electron gas in the leads within a single narrow energy window. Applying our model to experimental data allows for the determination of physical parameters of the pump and its operation; such as the capture energy of the electrons, the broadening of the quantised Landau levels in the leads, and the quantum lifetime of the electrons.