A cavity-mediated reconfigurable coupling scheme for superconducting qubits

• URL: http://arxiv.org/abs/2602.08869v1
• Date: Mon, 09 Feb 2026 16:30:30 GMT
• Title: A cavity-mediated reconfigurable coupling scheme for superconducting qubits
• Authors: Shinyoung Hwang, Sangyeon Lee, Eunjong Kim,
• Abstract summary: We introduce a cavity-mediated coupling architecture in which a shared cavity mode, accessed through tunable qubit-cavity couplers, enables dynamically reconfigurable interactions between non-adjacent qubits.<n>We show that high-fidelity iSWAP and CZ gates can be performed within 50 ns with simulated coherent error below $10-4$, while residual $ZZ$ interaction during idling remains below a few kilohertz.<n>This approach provides a practical route toward enhanced interaction flexibility in superconducting quantum processors and may serve as a useful building block for devices that benefit from selective non-local coupling.
• Score: 0.0
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: Superconducting qubits have achieved remarkable progress in gate fidelity and coherence, yet their typical nearest-neighbor connectivity presents constraints for implementing complex quantum circuits. Here, we introduce a cavity-mediated coupling architecture in which a shared cavity mode, accessed through tunable qubit-cavity couplers, enables dynamically reconfigurable interactions between non-adjacent qubits. By selectively activating the couplers, we demonstrate that high-fidelity iSWAP and CZ gates can be performed within 50 ns with simulated coherent error below $10^{-4}$, while residual $ZZ$ interaction during idling remains below a few kilohertz. Extending to a four-qubit system, we also simulate gates between every qubit pair by selectively enabling the couplers with low qubit crosstalk. This approach provides a practical route toward enhanced interaction flexibility in superconducting quantum processors and may serve as a useful building block for devices that benefit from selective non-local coupling.

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