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arXiv · 2312.01298

Noiselessly amplified thermal states and after multi-photon addition or subtraction

Xue-feng Zhan·Xue-xiang Xu
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Abstract

In this paper, we introduce a noiselessly amplified thermal state (ATS), by operating the noiseless amplification operator ($g^{\hat{n}}$) on the thermal state (TS) with corresponding mean photon number (MPN) $\bar{n}$. Actually, the ATS is an new TS with MPN $\bar{N}=g^{2}\bar{n}/[1-\bar{n}\left(g^{2}-1\right)]$. Furthermore, we introduce photon-added-ATS (PAATS) and photon-subtracted-ATS (PSATS) by operating $m$-photon addition ($\hat{a}^{\dag m}$) and $m$-photon subtraction ($\hat{a}^{m}$) on the ATS, respectively. We study photon number distributions (PNDs), purities, and Wigner functions (WFs) for all these states.

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Xue-feng Zhan, Xue-xiang Xu. 2023-12-03. Noiselessly amplified thermal states and after multi-photon addition or subtraction. https://arxiv.org/abs/2312.01298

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