학술논문

Strong-Coupling Effects on Specific Heat in the BCS–BEC Crossover.
Document Type
Article
Source
Journal of Low Temperature Physics. Jul2019, Vol. 196 Issue 1/2, p111-118. 8p.
Subject
*BCS-BEC crossover
*ELECTRON gas
*TRANSITION temperature
*SUPERFLUIDITY
*PHYSICS
Language
ISSN
0022-2291
Abstract
We theoretically investigate strong-coupling effects on specific heat at constant volume C V in a superfluid Fermi gas with a tunable interaction associated with Feshbach resonance. Including fluctuations of the superfluid order parameter within the strong-coupling theory developed by Nozières and Schmitt-Rink, we calculate the temperature dependence of C V at the unitarity limit in the superfluid phase. We show that, in the low-temperature region, T 3 -behavior is shown in the temperature dependence of C V . This result indicates that the low-lying excitations are dominated by the gapless Goldstone mode, associated with the phase fluctuations of the superfluid order parameter. Since the Goldstone mode is one of the most fundamental phenomena in the Fermionic superfluidity, our results are useful for further understanding how the pairing fluctuations affect physical properties in the BCS–BEC crossover physics below the superfluid transition temperature. [ABSTRACT FROM AUTHOR]