Nonreciprocal universal photon blockade in an asymmetrical cavity
Phys. Rev. A 113, 063729 – Published 18 June, 2026
DOI: https://doi.org/10.1103/v7jc-jsv5
Abstract
Inspired by the distinctive properties of universal photon blockade (UPB), we propose a two-photon Jaynes-Cummings model in an asymmetric cavity to achieve quantum nonreciprocity. Through theoretical analysis, we establish direction-dependent optimal conditions for perfect UPB in weak-driving limitation and subsequently validate these conditions through numerical solutions of the master equation. Our results demonstrate that in asymmetric cavities, the optimal atom-cavity coupling strength for UPB exhibits directionality, leading to a corresponding directional dependence in the equal-time second-order correlation function of the cavity field. This directional anisotropy enables remarkable photon statistics in the weak-coupling case: output photons display bunching in one propagation direction while manifesting antibunching in the opposite direction, thereby achieving giant nonreciprocal UPB. Our findings provide a framework for engineering robust quantum nonreciprocal effects, with promising applications in quantum information processing and optical communication systems.
