Resonant Photon-Assisted Tunneling Through a Double Quantum Dot: An Electron Pump From Spatial Rabi Oscillations

TL;DR

This paper presents an exact calculation of the nonlinear current in a double quantum dot system driven by ac and dc voltages, demonstrating resonant electron pumping via Rabi oscillations.

Contribution

It introduces an exact theoretical analysis of photon-assisted tunneling and electron pumping in double quantum dots using the Keldysh Green function method.

Findings

Maximum pumping current occurs when lead coupling matches Rabi frequency.

System acts as an efficient electron pump on resonance.

Exact nonlinear current calculation for arbitrary ac and dc voltages.

Abstract

The time average of the fully nonlinear current through a double quantum dot, subject to an arbitrary combination of ac and dc voltages, is calculated exactly using the Keldysh nonequilibrium Green function technique. When driven on resonance, the system functions as an efficient electron pump due to Rabi oscillation between the dots. The pumping current is maximum when the coupling to the leads equals the Rabi frequency.