A fault-tolerant addressable spin qubit in a natural silicon quantum dot

TL;DR

This paper demonstrates a fault-tolerant, addressable spin qubit in natural silicon quantum dots with high fidelity, achieved through optimized design and fast control, bridging the gap with purified silicon systems.

Contribution

It introduces a novel design for fault-tolerant spin qubits in natural silicon, achieving high fidelity comparable to purified silicon systems.

Findings

Achieved a qubit fidelity of 99.6%.

Rabi oscillation quality factor Q = 140 at 10 MHz.

Demonstrated fault-tolerant operation in natural silicon.

Abstract

Fault-tolerant quantum operation is a key requirement for the development of quantum computing. This has been realized in various solid-state systems including isotopically purified silicon which provides a nuclear spin free environment for the qubits, but not in industry standard natural (unpurified) silicon. Here we demonstrate an addressable fault-tolerant qubit using a natural silicon double quantum dot with a micromagnet optimally designed for fast spin control. This optimized design allows us to achieve the optimum Rabi oscillation quality factor Q = 140 at a Rabi frequency of 10 MHz in the frequency range two orders of magnitude higher than that achieved in previous studies. This leads to a qubit fidelity of 99.6 %, which is the highest reported for natural silicon qubits and comparable to that obtained in isotopically purified silicon quantum-dot-based qubits. This result can inspire contributions from the industrial and quantum computing communities.