Geometric protected quantum bus in a hybrid superconducting-spin architecture
Phys. Rev. Applied 25, 044010 – Published 3 April, 2026
DOI: https://doi.org/10.1103/dftf-g4kc
Abstract
Hybrid quantum systems integrating spin qubits and superconducting qubits have emerged as promising candidates for scalable quantum information processing. In hybrid architectures, the development of high-fidelity quantum buses is a crucial but challenging element. Here we design a quantum bus that utilizes engineered virtual photons to couple spin and superconducting modules. We tailor the driving pulse to accelerate the evolution of the hybrid system in a noncyclic geometric phase way. We demonstrate the enhanced functionality of the quantum bus in three ways. First, we propose a scheme for realizing universal gate operation between different modules in a short time of 40 ns with 99.05% fidelity, exceeding the fault-tolerance threshold. Second, we theoretically demonstrate the preparation of remote entanglement between different modules with a fidelity of 99.21%, a valuable resource for hybrid architectures. Finally, we show the robustness of this approach to control parameter imperfections compared to usual dynamical pulses. These results provide a toolbox for fast, high-fidelity, and robust quantum information processing on hybrid platforms.