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Quantum Disentanglement in Long-range Orders and Spontaneous Symmetry Breaking

Yu Shi
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Abstract

We investigate the nature of quantum entanglement in long-range orders and spontaneous symmetry breaking. It is shown that diminishing of entanglement between the condensate mode and the rest of the system underlies off-diagonal long-range order, which is the hallmark of superconductivity and Bose-Einstein condensation. It is also revealed that disentanglement underlies various cases of long-range order and spontaneous symmetry breaking. In the course of the discussion, we also present some ideas on characterizing entanglement in many-body systems. Especially, it is shown how the connected correlation functions can be used in characterizing entanglements in a pure state.

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Yu Shi. 2003-01-31. Quantum Disentanglement in Long-range Orders and Spontaneous Symmetry Breaking. https://doi.org/10.1016/s0375-9601(03)00128-2

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