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Spatial Entanglement From Off-Diagonal Long Range Order in a BEC

Libby Heaney·Janet Anders·Dagomir Kaszlikowski·Vlatko Vedral
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Abstract

We investigate spatial entanglement - particle-number entanglement between regions of space - in an ideal Bosonic gas. We quantify the amount spatial entanglement around the transition temperature for condensation by probing the gas with two localised two-level systems. We show that spatial entanglement in the gas is directly related to filling of the ground state energy level and therefore to the off-diagonal long-range order of the system and the onset of condensation.

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Libby Heaney, Janet Anders, Dagomir Kaszlikowski, Vlatko Vedral. 2007-09-26. Spatial Entanglement From Off-Diagonal Long Range Order in a BEC. https://doi.org/10.1103/physreva.76.053605

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