Derivation of the effective action of a dilute Fermi gas in the unitary limit of the BCS-BEC crossover

Adriaan M. J. Schakel

doi:10.1016/j.aop.2010.09.005

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arXiv · 0912.1955

Derivation of the effective action of a dilute Fermi gas in the unitary limit of the BCS-BEC crossover

Adriaan M. J. Schakel

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Abstract

The effective action describing the gapless Nambu-Goldstone, or Anderson-Bogoliubov, mode of a zero-temperature dilute Fermi gas at unitarity is derived up to next-to-leading order in derivatives from the microscopic theory. Apart from a next-to-leading order term that is suppressed in the BCS limit, the effective action obtained in the strong-coupling unitary limit is proportional to that in the weak-coupling BCS limit.

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Adriaan M. J. Schakel. 2009-12-10. Derivation of the effective action of a dilute Fermi gas in the unitary limit of the BCS-BEC crossover. https://doi.org/10.1016/j.aop.2010.09.005

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