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arXiv · 1110.3417

Effects of three-body scattering processes on BCS-BEC crossover

Raka Dasgupta
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Abstract

We investigate the BCS-BEC crossover taking into account an additional three-body interaction, which is essentially the scattering between the Cooper pairs and the newly formed bosons. We show that if the two-body interaction is attractive, the presence of this additional three-body term makes the crossover process a nonreversible one. Starting from a stable Bose-Einstein condensate (BEC) state, crossover to BCS can be achieved; but if the BCS state is the starting point, instead of a stable BEC region, what the system crosses over to is a metastable condensed state.

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Raka Dasgupta. 2011-10-15. Effects of three-body scattering processes on BCS-BEC crossover. https://doi.org/10.1103/physreva.82.063607

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