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arXiv · 2112.14425

Enhanced Optimal Quantum Communication by Generalized Phase Shift Keying Coherent Signal

Min Namkung·Jeong San Kim
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Abstract

It is well known that the maximal success probability of the binary quantum communication can be improved by using a sub-Poissonian non-standard coherent state as an information carrier. In the present article, we consider the quantum communication with $N$-ary phase shift keying ($N$-PSK) signal for an arbitrary positive integer $N>1$. By using non-standard coherent state, we analytically provide the maximal success probability of the quantum communication with $N$-PSK. Unlike the binary case, we show that even super-Poissonianity of non-standard coherent state can improve the maximal success probability of $N$-PSK quantum communication.

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Min Namkung, Jeong San Kim. 2021-12-29. Enhanced Optimal Quantum Communication by Generalized Phase Shift Keying Coherent Signal. https://doi.org/10.1103/physreva.105.042428

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