An Adiabatic Quantum Electron Pump

TL;DR

This paper reports an adiabatic quantum electron pump that generates dc current or voltage through cyclic potential deformation in quantum dots, with responses influenced by phase, frequency, and external parameters.

Contribution

It introduces a quantum pumping mechanism in open quantum dots and explores its dependence on various physical parameters, highlighting new insights into adiabatic quantum transport.

Findings

Pumping voltage is sinusoidal in phase difference.

Amplitude increases linearly with frequency.

Fluctuations depend on magnetic field and temperature.

Abstract

A quantum pumping mechanism which produces dc current or voltage in response to a cyclic deformation of the confining potential in an open quantum dot is reported. The voltage produced at zero current bias is sinusoidal in the phase difference between the two ac voltages deforming the potential and shows random fluctuations in amplitude and direction with small changes in external parameters such as magnetic field. The amplitude of the pumping response increases linearly with the frequency of the deformation. Dependencies of pumping on the strength of the deformations, temperature, and breaking of time-reversal symmetry are also investigated.