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arXiv · 1908.10648

Local-field Theory of the BCS-BEC Crossover

Pietro Maria Bonetti·Maria Luisa Chiofalo
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Abstract

We develop a self-consistent theory unifying the description of a quantum Fermi gas in the presence of a Fano-Feshbach resonance in the whole phase diagram ranging from BCS to BEC type of superfluidity and from narrow to broad resonances, including the fluctuations beyond mean field. Our theory covers a part of the phase diagram which is not easily accessible by Quantum Monte Carlo simulations and is becoming interesting for a new class of experiments in cold atoms.

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Pietro Maria Bonetti, Maria Luisa Chiofalo. 2019-08-28. Local-field Theory of the BCS-BEC Crossover. https://arxiv.org/abs/1908.10648

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