On-Chip Quantum Dot Light Source for Quantum State Readout

TL;DR

This paper demonstrates a novel on-chip quantum dot micromaser-based charge state detection method that enhances scalability for quantum state readout without requiring cavity input fields.

Contribution

It introduces a new on-chip quantum dot micromaser technique for charge detection, eliminating the need for cavity input fields and improving scalability of quantum readout.

Findings

Microwave radiation from a DQD micromaser can detect charge states.

The method operates without cavity input fields.

Potential for scalable quantum state readout technologies.

Abstract

We use microwave radiation generated by a semiconductor double quantum dot (DQD) micromaser for charge state detection. A cavity is populated with n_c ~ 6000 photons by driving a current through an emitter DQD. These photons are used to sense the charge state of a target DQD that is located at the opposite end of the cavity. Charge dynamics in the target DQD influence the output power and emission frequency of the maser. Three different readout mechanisms are compared. The detection scheme requires no cavity input field and may potentially be used to improve the scalability of semiconductor and superconducting qubit readout technologies.