Landau-Zener-Stuckelberg Interferometry of a Single Electron Charge Qubit

TL;DR

This paper demonstrates Landau-Zener-Stuckelberg interferometry on a single electron charge qubit in GaAs, revealing quantum coherence effects, photon-driven excitations, and the ability to control qubit states with microwave driving.

Contribution

It presents the first detailed experimental study of Landau-Zener-Stuckelberg interferometry on a single electron charge qubit, including observation of multi-photon processes and coherent tunneling control.

Findings

Observation of coherent destruction of tunneling.

Detection of up to 17-photon absorption processes.

Good agreement between simulations and experimental data.

Abstract

We perform Landau-Zener-Stuckelberg interferometry on a single electron GaAs charge qubit by repeatedly driving the system through an avoided crossing. We observe coherent destruction of tunneling, where periodic driving with specific amplitudes inhibits current flow. We probe the quantum dot occupation using a charge sensor, observing oscillations in the qubit population resulting from the microwave driving. At a frequency of 9 GHz we observe excitation processes driven by the absorption of up to 17 photons. Simulations of the qubit occupancy are in good agreement with the experimental data.