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arXiv · 0803.2265

Macroscopic Superpositions of Phase States with Bose-Einstein Condensates

F. Piazza·L. Pezze'·A. Smerzi
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Abstract

Quantum superpositions of macroscopically distinguishable states having distinct phases can be created with a Bose-Einstein condensate trapped in a periodic potential. The experimental signature is contained in the phase distribution of the interference patterns obtained after releasing the traps. Moreover, in the double well case, this distribution exhibits a dramatic dependence on the parity of the total number of atoms. We finally show that, for single well occupations up to a few hundred atoms, the macroscopic quantum superposition can be robust enough against decoherence to be experimentally revealable within current technology.

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F. Piazza, L. Pezze', A. Smerzi. 2008-11-06. Macroscopic Superpositions of Phase States with Bose-Einstein Condensates. https://doi.org/10.1103/physreva.78.051601

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