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arXiv:2601.01519 · Annalen der Physik

Entropy and Variance Squeezing of V-type Atom in Dissipative Cavity

Zijin Liang, Qiying Pan, Hong-Mei Zou, Chenrui Bi

quant-phSubmitted Jan 4, 2026• Announced Jan 6, 2026• 0 citations
v1 · Jan 4, 2026v2 · Aug 4, 2026v3 · Aug 5, 2026v4 · Sep 30, 2026
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Abstract

Based on Ref.\cite{Riccardi A}, we investigate the entropy and variance squeezing of a V-type atom in a dissipative cavity, and discuss the influences of parameters including the spontaneously generated interference (SGI) ($θ$), the cavity-environment coupling ($γ_0/κ$) and the atom-cavity detuning ($Δ$) on the atomic squeezing by using different initial states. The results show that no squeezing of $S_y$ occurs under any condition and that variance squeezing of $S_x$ appears only when $Δ>0$. Entropy squeezing quantifies quantum fluctuations more precisely than variance squeezing. Moreover, the atomic squeezing of $S_x$ clearly depends on $θ$, $γ_0/κ$, $Δ$ and the initial state. These findings are meaningful for quantum information processing as an ultra-low-noise resource.

Journal reference
Annalen der Physik 538(10), 70294 (2026)
DOI
10.1002/andp.70294

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