Strong-Coupling Effects on Specific Heat in the BCS–BEC Crossover

Daisuke Inotani, Pieter van Wyk, Yoji Ohashi

Research output: Contribution to journalArticle

Abstract

We theoretically investigate strong-coupling effects on specific heat at constant volume CV 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 CV at the unitarity limit in the superfluid phase. We show that, in the low-temperature region, T3-behavior is shown in the temperature dependence of CV. 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.

Original languageEnglish
Pages (from-to)111-118
Number of pages8
JournalJournal of Low Temperature Physics
Volume196
Issue number1-2
DOIs
Publication statusPublished - 2019 Jul 15

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Specific heat
crossovers
specific heat
Superfluid helium
temperature dependence
superfluidity
Temperature
Superconducting transition temperature
Physics
Physical properties
physical properties
Gases
transition temperature
physics
gases
excitation
interactions

Keywords

  • BCS–BEC crossover
  • Goldstone mode
  • Specific heat
  • Ultracold Fermi gas

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics
  • Materials Science(all)
  • Condensed Matter Physics

Cite this

Strong-Coupling Effects on Specific Heat in the BCS–BEC Crossover. / Inotani, Daisuke; van Wyk, Pieter; Ohashi, Yoji.

In: Journal of Low Temperature Physics, Vol. 196, No. 1-2, 15.07.2019, p. 111-118.

Research output: Contribution to journalArticle

Inotani, Daisuke ; van Wyk, Pieter ; Ohashi, Yoji. / Strong-Coupling Effects on Specific Heat in the BCS–BEC Crossover. In: Journal of Low Temperature Physics. 2019 ; Vol. 196, No. 1-2. pp. 111-118.
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