Goldstone and Higgs Hydrodynamics in the BCS–BEC Crossover
Abstract
:1. Introduction
2. Functional Integration for the BCS–BEC Crossover
2.1. Loop Expansion and Gaussian Approximation
2.2. Beyond-Mean-Field Grand Potential
3. Low-Energy Gaussian Action
3.1. Connection with the Popov’s Hydrodynamic Action Functional
3.2. First Sound Velocity from Thermodynamics
4. Conclusions
Conflicts of Interest
References
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Salasnich, L. Goldstone and Higgs Hydrodynamics in the BCS–BEC Crossover. Condens. Matter 2017, 2, 22. https://doi.org/10.3390/condmat2020022
Salasnich L. Goldstone and Higgs Hydrodynamics in the BCS–BEC Crossover. Condensed Matter. 2017; 2(2):22. https://doi.org/10.3390/condmat2020022
Chicago/Turabian StyleSalasnich, Luca. 2017. "Goldstone and Higgs Hydrodynamics in the BCS–BEC Crossover" Condensed Matter 2, no. 2: 22. https://doi.org/10.3390/condmat2020022