Robust Transferring Entangled States Between Multiple Superconducting Qubits and Remote Optical Cavities in the Hybrid System

Based on the hybrid system, we propose a network device to achieve entanglement transfer between multiple superconducting qubits and spatially separated optical cavities. The network model consists of nodes, each equipped with an optical fiber linked to the remote optical cavity. In the central microwave cavity of the network, several superconducting qubits are placed. The protocol begins by initializing superconducting qubits in an entangled state (Bell or GHZ state). By leveraging microwave‐optical photon converters and optical fibers, the entangled states are transferred to spatially separated optical cavities. As a specific example, we numerically demonstrate that the high‐fidelity transfer of a Bell state of superconducting qubits onto spatially separated optical cavities is achievable within the present‐day circuit QED technology. Besides, it is worthy to note that when the dissipation is negligible, the entangled Bell state of spatially separated optical cavities can be transferred back onto superconducting qubits by performing reverse operations. Finally, this proposal is quite general and can be extended to other hybrid systems with resembling level structure. This approach provides a promising candidate for long‐distance entanglement distribution in hybrid quantum networks with potential applications in scalable quantum communication and information processing.