Geometric two-qubit gates in silicon-based double quantum dots

TL;DR

This paper proposes a theoretical method for implementing high-fidelity geometric two-qubit gates in silicon spin qubits, demonstrating fidelities over 99% and robustness against charge noise, advancing quantum computing in silicon.

Contribution

It introduces a feasible strategy for geometric two-qubit gates in silicon quantum dots, considering experimental conditions and noise, with analytical and numerical validation.

Findings

Fidelities surpassing 99% under experimental noise levels

Geometric gates outperform dynamical operations in robustness

Implementation is feasible in current experimental setups

Abstract

Achieving high-fidelity two-qubit gates is crucial for spin qubits in silicon double quantum dots. However, the two-qubit gates in experiments are easily suffered from charge noise, which is still a key challenge. Geometric gates which implement gate operations employing pure geometric phase are believed to be a powerful way to realize robust control. In this work, we theoretically propose feasible strategy to implement geometric two-qubit gates for silicon-based spin qubits considering experimental control environments. By working in the suitable region where the local magnetic field gradient is much larger than the exchange interaction, we are able to implement entangling and non-entangling geometric gates via analytical and numerical methods. It is found that the implemented geometric gates can obtain fidelities surpassing 99\% for the noise level related to the experiments. Also, they can outperform the dynamical opertations. Our work paves a way to implement high-fidelity geometric gate for spin qubits in silicon.