Crosstalk-robust superconducting two-qubit geometric gates using tunable couplers

TL;DR

This paper introduces a tunable coupler-based geometric gate scheme for superconducting qubits that enhances crosstalk suppression, speed, and robustness against imperfections, advancing scalable quantum computing.

Contribution

It proposes a novel coupler-assisted geometric gate design with additional parametric controls for optimized crosstalk suppression and robustness.

Findings

Effective crosstalk error suppression demonstrated in simulations

Fast gate operations achieved with high fidelity

Robust performance against qubit frequency drift and decoherence

Abstract

The design of coupler-based superconducting two-qubit gates simplifies circuit layout and alleviate frequency crowding, thereby enhancing the scalability and flexibility of quantum chips. However, in such architectures, a trade-off often exists between suppressing crosstalk and reducing gate duration, and how to achieve synergistic optimization of both remains an open challenge. To address this, this paper proposes a coupler-assisted superconducting two-qubit geometric gate scheme oriented towards crosstalk robustness. By introducing additional parametric degrees of freedom, the scheme steers the system evolution along desired trajectories, thereby flexibly avoiding crosstalk-sensitive operational regions. Numerical simulations demonstrate that the proposed scheme can effectively suppress crosstalk errors while enabling fast gate operations, and exhibits strong robustness against typical experimental imperfections such as qubit frequency drift. Moreover, even when accounting for unavoidable high-frequency oscillation terms and qubit decoherence in realistic physical systems, our crosstalk-robust two-qubit geometric gates still achieve high fidelity. This work provides a feasible pathway toward robust and efficient two-qubit gate implementation in superconducting quantum computation.