Path Integral Treatment of Fluctuations in the BCS-BEC Crossover in Superfluid Fermi Gases

H. Vivas

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Path Integral Treatment of Fluctuations in the BCS-BEC Crossover in Superfluid Fermi Gases

H. Vivas

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Abstract

By using a Path Integral formalism, we study the fluctuating fields in the order parameter for a 3D uniform Fermi gas at T<Tc. The BCS-BEC crossover condition is included into the analysis in the framework of the usual s-wave scattering approximation. The general expressions for the temperature dependence of the partition function and the quadratic average in the fluctuations fields are explicitly established in terms of the BCS-Gor'kov correlation propagators.

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H. Vivas. 2011-06-30. Path Integral Treatment of Fluctuations in the BCS-BEC Crossover in Superfluid Fermi Gases. https://arxiv.org/abs/cond-mat/0504600

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