A few-electron quadruple quantum dot in a closed loop

TL;DR

This paper demonstrates a quadruple quantum dot system that allows precise control of single-electron transfer along a closed loop, paving the way for electron spin manipulation via spin-orbit interaction.

Contribution

It introduces a novel quadruple quantum dot device in a square configuration capable of controlling single-electron transfer on a closed path.

Findings

Successfully reached the few-electron regime in the quadruple dot system.

Achieved control over electron population in each quantum dot with gate voltages.

Demonstrated transfer of a single electron along a closed loop.

Abstract

We report the realization of a quadruple quantum dot device in a square-like configuration where a single electron can be transferred on a closed path free of other electrons. By studying the stability diagrams of this system, we demonstrate that we are able to reach the few-electron regime and to control the electronic population of each quantum dot with gate voltages. This allows us to control the transfer of a single electron on a closed path inside the quadruple dot system. This work opens the route towards electron spin manipulation using spin-orbit interaction by moving an electron on complex paths free of electrons