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arXiv · 1110.5444

Distinguishing mesoscopic quantum superpositions from statistical mixtures in periodically shaken double wells

Christoph Weiss
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Abstract

For Bose-Einstein condensates in double wells, N-particle Rabi-like oscillations often seem to be damped. Far from being a decoherence effect, the apparent damping can indicate the emergence of quantum superpositions in the many-particle quantum dynamics. However, in an experiment it would be difficult to distinguish the apparent damping from decoherence effects. The present paper suggests using controlled periodic shaking to quasi-instantaneously switch the sign of an effective Hamiltonian, thus implementing an `echo' technique which distinguishes quantum superpositions from statistical mixtures. The scheme for the effective time-reversal is tested by numerically solving the time-dependent N-particle Schrodinger equation.

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Christoph Weiss. 2011-10-25. Distinguishing mesoscopic quantum superpositions from statistical mixtures in periodically shaken double wells. https://doi.org/10.1088/0953-4075%2F45%2F2%2F021002

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