Proximity-Driven Photon Tunneling in Chiral Quantum Hybrid Systems

Chiral resonator systems have been shown to exhibit optical activity and asymmetric mode coupling, yet a quantum-mechanical description of photon tunneling between such elements remains limited. Here, we experimentally investigate proximity-driven photon tunneling in pairs of inverted circular split-ring resonators with discrete chiral orientations (0°, 90°, 180°, 270°) coupled through a shared photon guide. By tuning the inter-resonator spacing, we observe chirality-dependent mode hybridization, spectral splitting, and interference effects in microwave transmission spectra. Full-wave simulations and a circuit quantum electrodynamics model reproduce these behaviors and predict coupling-sign reversal arising from phase inversion. The combined experimental–theoretical results uniquely demonstrate coherent control of photon tunneling through geometry and excitation phase, advancing the design of reconfigurable photonic and chiral quantum communication platforms.