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Squeezing-Enhanced Phase-Shift-Keyed Binary Communication in Noisy Channels^{ †}

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## Abstract

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## Author Contributions

## References

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**Figure 1.**(

**a**) The Helstrom bound for DSSs as function of the squeezing fraction $\beta $ and the channel energy N. The plane corresponds to the Helstrom bound for coherent states and the solid line to the threshold ${\beta}_{\mathrm{th}}\left(N\right)$. (

**b**) The homodyne-detection error probability ${P}_{\mathrm{err}}$ as a function of $\beta $ for different values of the channel energy N. The plane corresponds to the minimum error probability achievable using only coherent states and homodyne detection and the solid line to the threshold ${\beta}_{\mathrm{th}}\left(N\right)$. Figures adapted from [9].

**Figure 2.**Comparison between the error probability ${P}_{\mathrm{err}}$ (solid lines) and the Helstrom bound (dashed lines) as functions of the noise parameter $\sigma $ for the DSS and the coherent state. We set $\beta ={\beta}_{\mathrm{opt}}\left(N\right)=N/(2N+1)$ and $N=2$. The shaded region refers to the range of the noise parameter values such that the homodyne probability with DSS is below the Helstrom bound with coherent states. Figures adapted from [9].

**Figure 3.**(

**a**) Error probability ${P}_{\mathrm{err}}$ of the homodyne receiver as a function of $\beta $ and the purity $\mu $ for different values of the noise parameter $\sigma $. (

**b**) Threshold value of the squeezing fraction ${\beta}_{\mathrm{th}}$ as a function of the purity $\mu $ for different values of $\sigma $. The shaded regions refer to the pairs of parameters $(\mu ,\beta )$ for which DSSs outperform coherent states. Note that ${(1+2N)}^{-1}\le \mu \le 1$. In both the panels we set $N=2$. Figures adapted from [9].

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**MDPI and ACS Style**

Chesi, G.; Olivares, S.; Paris, M.G.A.
Squeezing-Enhanced Phase-Shift-Keyed Binary Communication in Noisy Channels. *Proceedings* **2019**, *12*, 58.
https://doi.org/10.3390/proceedings2019012058

**AMA Style**

Chesi G, Olivares S, Paris MGA.
Squeezing-Enhanced Phase-Shift-Keyed Binary Communication in Noisy Channels. *Proceedings*. 2019; 12(1):58.
https://doi.org/10.3390/proceedings2019012058

**Chicago/Turabian Style**

Chesi, Giovanni, Stefano Olivares, and Matteo G. A. Paris.
2019. "Squeezing-Enhanced Phase-Shift-Keyed Binary Communication in Noisy Channels" *Proceedings* 12, no. 1: 58.
https://doi.org/10.3390/proceedings2019012058