English

A cavity-mediated reconfigurable coupling scheme for superconducting qubits

Quantum Physics 2026-02-10 v1

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 10410^{-4}, while residual ZZZZ 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.

Keywords

Cite

@article{arxiv.2602.08869,
  title  = {A cavity-mediated reconfigurable coupling scheme for superconducting qubits},
  author = {Shinyoung Hwang and Sangyeon Lee and Eunjong Kim},
  journal= {arXiv preprint arXiv:2602.08869},
  year   = {2026}
}
R2 v1 2026-07-01T10:28:15.980Z