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arXiv · 1203.0595

Entanglement and nonclassicality of photon-added two-mode squeezed thermal state

Li-Yun Hu·Fang Jia·Zhi-Ming Zhang
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Abstract

We introduce a kind of entangled state---photon-addition two-mode squeezed thermal state (TMSTS) by adding photons to each mode of the TMSTS. Using the P-representation of thermal state, the compact expression of the normalization factor is derived, a Jacobi polynomial. The nonclassicality is investigated by exploring especially the negativity of Wigner function. The entanglement is discussed by using Shchukin-Vogel criteria. It is shown that the photon-addtion to the TMSTS may be more effective for the entanglement enhancement than the photon-subtraction from the TMSTS. In addition, the quantum teleportation is also examined, which shows that symmetrical photon-added TMSTS may be more useful for quantum teleportation than the non-symmetric case.

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Li-Yun Hu, Fang Jia, Zhi-Ming Zhang. 2012-03-03. Entanglement and nonclassicality of photon-added two-mode squeezed thermal state. https://doi.org/10.1364/josab.29.001456

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