Journal of the Optical Society of America B

Three-mode quantum criteria of exceptional points in energy-level cascaded four-wave mixing

Qingyu Chen, Rui Zhuang, Sinong Liu, Jiaxuan Wei, Guobin Liu, Zhou Feng, Yanpeng Zhang

Published Jul 11, 2025• 1 citation

Abstract

In recent years, multi-mode quantum entanglement and quantum squeezing have gained significant research interest. This paper successfully realizes quantitative control over the characteristic of quantum entanglement produced by cascaded parametrically amplified four-wave mixing (PA-FWM) through adjusting the Rabi frequency and dephasing rate of dressing fields, in which PT and anti-PT symmetry breaking, respectively, induce distinct energy-level quantization and generate coherent multi-channels in the atomic transition of the natural non-Hermitian system. Further simulations of the Duan criterion, the PPT criterion, and quantum steering have been implemented to investigate the properties of generated multi-mode entanglement when employing schemes featuring EPR injection and degenerate FWM. The comparison reveals that EPR injection enhances the entanglement of the injected EPR mode while suppressing the entanglement of other modes. Distinctive schemes of degenerate FWM and two pairs of EPR injections would successfully transform two originally separate modes into a pair of entangled modes, exhibiting significant research value in quantum metrology and relevant applications.

DOI: 10.1364/josab.561786

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