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arXiv · 2511.04927

Universal and Tunable Sudden Freezing of Entanglement Volume

Luchang Niu·Joseph H. Eberly
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Abstract

In a system where two identical two-level atoms interact with their common one-mode cavity field, it is shown that entanglement can become abruptly frozen in time, remaining at a constant value for a period of time until it begins to thaw from this value from the entanglement sharing perspective [Ding et al., Phys. Rev. A 103, 032418 (2021)]. We generalize this exotic behavior of entanglement sharing dynamics to more general systems with arbitrary N qubits, instead of restricting to the atom-cavity mode interaction system. We also demonstrate methods to control the entanglement freezing time and freezing value, and we discover a nontrivial dynamics where entanglement is frozen permanently. In addition, we show that this phenomenon is not a coincidence but a universal feature in a variety of systems with a geometric explanation of the mechanisms.

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Luchang Niu, Joseph H. Eberly. 2025-11-07. Universal and Tunable Sudden Freezing of Entanglement Volume. https://arxiv.org/abs/2511.04927

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