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arXiv · 2109.12145

Enhancement of non-Gaussianity and nonclassicality of photon added displaced Fock state: A quantitative approach

Priya Malpani·Kishore Thapliyal·J. Banerji·Anirban Pathak
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Abstract

Non-Gaussian and nonclassical states and processes are already found to be important resources for performing various tasks related to quantum gravity and quantum information processing. The effect of non-Gaussianity inducing operators on the nonclassicality of quantum states has also been studied rigorously. Considering these facts, a quantitative analysis of the nonclassical and non-Gaussian features is performed here for photon added displaced Fock state, as a test case, using a set of measures like entanglement potential, Wigner Yanese skew information, Wigner logarithmic negativity and relative entropy of non-Gaussianity. It is observed that photon addition (Fock parameter) significantly increases the amount of nonclassicalty and non-Gaussianity for small (large) values of the displacement parameter, which decreases both the quantum features monotonically. In this respect, the role of Fock parameter is found to be more prominent and stronger compared to photon addition. Finally, the dynamics of Wigner function under the effect of photon loss channel is used to show that only highly efficient detectors are able to detect Wigner negativity.

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Priya Malpani, Kishore Thapliyal, J. Banerji, Anirban Pathak. 2021-09-24. Enhancement of non-Gaussianity and nonclassicality of photon added displaced Fock state: A quantitative approach. https://arxiv.org/abs/2109.12145

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