Influence of pump brightness,self-Kerr and cross-Kerr effects on the entanglement of partially degenerate triple-photon state  

作　　者：Da Zhang Zhihong Ren 

机构地区：[1]School of Physics and Information Engineering,Shanxi Normal University,Taiyuan 030031,China

出　　处：《Communications in Theoretical Physics》2023年第10期45-50,共6页理论物理通讯（英文版）

基　　金：the National Natural Science Foundation of China(12204293);Applied Basic Research Program in Shanxi Province(No.202203021212387)。

摘　　要：Recently,partially degenerate triple-photon states(TPS)generated by the third-order spontaneous parametric down-conversion have been observed in a superconducting cavity(2020,Phys.Rev.X 10,011011).Their non-Gaussian entanglement properties,characterized by a series of high-order covariance matrices,have also been theoretically revealed.Here,we use the non-Gaussian entanglement criterion proposed in(2021,Phy.Rev.Lett.127,150502)and the logarithmic negativity to study the effect of pump brightness,self-Kerr and cross-Kerr interactions on the entanglement of partially degenerate TPS(PDTPS).We find that the brighter the pump,the easier the entanglement of PDTPS leap to higher-order covariance matrices.Although both self-Kerr and cross-Kerr interactions induce nonlinear phase shifts and weaken the entanglement of PDTPS,cross-Kerr interactions can effectively raise the threshold of entanglement loaded on the third-order covariance matrix.These results can contribute to our understanding of the mechanism of the generation of unconditional non-Gaussian entanglement.

关 键 词：non-Gaussian entanglement triple-photon states high-order covariance matrices cross-Kerr effect 

分 类 号：O431.2[机械工程—光学工程]