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Journal of Modern Physics

Tunable Single-Photon Nonreciprocal Transmission and Directional Routing in a Microresonator-Waveguide System with Multiple Coupling Points

Jinsong Huang, Le Zhang, Hongwu Huang

Published Jan 1, 2026• 1 citation
Publisher

Abstract

We investigate the controllable single-photon transport via a microresonator coupled to two meandering waveguides at multiple coupling points. Using the analytical expressions of the single-photon scattering amplitudes obtained by the real-space Hamiltonian, the transport characteristics in the waveguide system are demonstrated. These results show that the perfectly nonreciprocal transmission in a single waveguide and the directional routing approaching the unity probability in two waveguides can be achieved by adjusting the resonator-waveguide coupling related to the phase parameter, arising from the phase-dependent interference effect of the multiple point couplings of the resonator. Our proposal may have wide potentials in quantum information processing.

DOI
10.4236/jmp.2026.172008

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