Non-invasive detection of the evolution of the charge states of a double dot system

TL;DR

This paper demonstrates a non-invasive method to monitor charge state evolution in coupled quantum dots, revealing electron movements, charge traps, and excited state transitions relevant for quantum computing.

Contribution

It introduces a non-invasive voltage probe technique to study charge dynamics in coupled quantum dots, including charge transfer and trap detection.

Findings

Detected electron movement between dots and charge traps

Identified electron transitions via excited states

Provided insights into charge state evolution in quantum dots

Abstract

Coupled quantum dots are potential candidates for qubit systems in quantum computing. We use a non-invasive voltage probe to study the evolution of a coupled dot system from a situation where the dots are coupled to the leads to a situation where they are isolated from the leads. Our measurements allow us to identify the movement of electrons between the dots and we can also identify the presence of a charge trap in our system by detecting the movement of electrons between the dots and the charge trap. The data also reveals evidence of electrons moving between the dots via excited states of either the single dots or the double dot molecule.