Unconventional photon blockade in a non-Hermitian indirectly coupled resonator system

Opt Express. 2023 Jan 16;31(2):1629-1640. doi: 10.1364/OE.477662.

Abstract

Photon blockade provides an effective way to realize the single-photon source, which attracts intensive attention in the fields of quantum optics and quantum information. Here in this study, we investigate photon blockade in a non-Hermitian indirectly coupled resonator system, which consists of a dissipative cavity and a Kerr nonlinear resonator coupled to two nano-scatters. We find that by tuning the coupling phase θ between the two resonators, the quantum interference could be induced on one side near the exceptional points (EPs), resulting in the unconventional photon blockade effect. Furthermore, it is noticed that the large Kerr nonlinearity is not always beneficial for unconventional photon blockades. There is an optimal threshold for the intensity of the Kerr nonlinearity and the phase angle θ for the appearance of the unconventional photon blockade effect. We believe the current study has substantial consequences for investigating the physical characteristics close to EPs and presents a novel method for developing integrated on-chip single-photon sources.