Automated All-RF Tuning for Spin Qubit Readout and Control

TL;DR

This paper presents an automated radio-frequency charge sensing method that significantly accelerates the tuning process of spin qubits in semiconductor quantum dots, enabling rapid identification and characterization of qubit regimes.

Contribution

It introduces a novel automated routine for spin qubit tuning using RF charge sensing, reducing tuning time and enabling high-throughput exploration of quantum circuits.

Findings

Median tuning time of ~15 minutes

Identified 12 charge transitions in under 17 hours

Automatically characterized gate-voltage dependence of key qubit parameters

Abstract

Efficient tuning of spin qubits remains a major bottleneck in scaling semiconductor quantum dot-based quantum processors. A key challenge is the rapid identification of gate voltage regimes suitable for qubit initialisation, control, and readout. Here, we leverage radio-frequency charge sensing to automate spin qubit tuning, achieving a median tuning time of approximately 15 minutes. In a single continuous run, our routine identifies spin qubits at 12 distinct charge transitions in under 17 hours. Beyond tuning, our routine autonomously acquires data revealing the gate-voltage dependence of the exchange interaction, dephasing time, and quality factor -- quantities that vary substantially between charge configurations. These results represent a step change in high-throughput spin qubit tuning and provide a foundation for a systematic and automated exploration of semiconductor quantum circuits.