Leakage-suppressed parametric entangling gates in a spin-resonator hybrid system
Phys. Rev. A 114, 022451 – Published 24 August, 2026
DOI: https://doi.org/10.1103/hrcl-68g8
Abstract
A hybrid quantum system comprising semiconductor spin qubits and superconducting resonators offers a practical route toward scalable quantum information processing. Achieving a high-fidelity entangling gate between spatially separated spin qubits is, however, both crucial and challenging. Here, we investigate an architecture where two multilevel singlet-triplet spin qubits are coupled to a common resonator. By combining virtual-photon-mediated interactions with parametric modulation, we design and theoretically demonstrate an exchange-type entangling gate between the spin qubits. Through numerical simulations, we analyze the detrimental effects of leakage errors on gate performance and propose an optimized pulse-shaping scheme that effectively suppresses leakage errors, achieving gate fidelities up to 96.9% under realistic experimental conditions. Our protocol can be directly applied to remote quantum state transfer and entangled-state preparation. These results highlight the generality of the proposed gate mechanism, establishing it as a powerful tool for quantum information processing in spin-resonator hybrid systems.
