# Gaussian entanglement witness and refined Werner-Wolf criterion for continuous variables

@inproceedings{Chen2022GaussianEW, title={Gaussian entanglement witness and refined Werner-Wolf criterion for continuous variables}, author={Xiao-yu Chen and Maoke Miao and Rui Yin and Jiantao Yuan}, year={2022} }

We use matched quantum entanglement witnesses to study the separable criteria of continuous variable states. The witness can be written as an identity operator minus a Gaussian operator. The optimization of the witness then is transformed to an eigenvalue problem of a Gaussian kernel integral equation. It follows a separable criterion not only for symmetric Gaussian quantum states, but also for non-Gaussian states prepared by photon adding to or/and subtracting from symmetric Gaussian states…

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