Non-adiabatic two-parameter charge and spin pumping in a quantum dot

TL;DR

This paper investigates non-adiabatic charge and spin transport in quantum dots driven by oscillating voltages and tunnel couplings, revealing interference effects and potential for electrical spin pumping.

Contribution

It generalizes the Tien and Gordon model to include simultaneous oscillations of voltages and tunnel couplings in quantum dots.

Findings

Interference effects between voltage and tunnel coupling oscillations.

Possibility of electrically pumping spin current with a static magnetic field.

Extension of the Tien and Gordon model to non-adiabatic two-parameter driving.

Abstract

We study DC charge and spin transport through a weakly coupled quantum dot, driven by a non-adiabatic periodic change of system parameters. We generalize the model of Tien and Gordon to simultaneously oscillating voltages and tunnel couplings. When applying our general result to the two-parameter charge pumping in quantum dots, we find interference effects between the oscillations of the voltage and tunnel couplings. Furthermore, we discuss the possibility to electrically pump a spin current in presence of a static magnetic field.