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arXiv · 1906.11799

Coherence assisted non-Gaussian measurement device independent quantum key distribution

Chandan Kumar·Jaskaran Singh·Soumyakanti Bose·Arvind
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Abstract

Non-Gaussian operations on two mode squeezed vacuum states (TMSV) in continuous variable measurement device independent quantum key distribution (CV-MDI-QKD) protocols have been shown to effectively increase the total transmission distances drastically. In this paper we show that photon subtraction on a two mode squeezed coherent (PSTMSC) state can further improve the transmission distances remarkably. To that end we also provide a generalized covariance matrix corresponding to PSTMSC, which has not been attempted before. We show that coherence, defined as the amount of displacement of vacuum state, along with non-Gaussianity can help improve the performance of prevalent CV-MDI-QKD protocols. Furthermore, since we use realistic parameters, our technique is experimentally feasible and can be readily implemented

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Chandan Kumar, Jaskaran Singh, Soumyakanti Bose, Arvind. 2019-07-01. Coherence assisted non-Gaussian measurement device independent quantum key distribution. https://doi.org/10.1103/physreva.100.052329

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