Spin-gap phenomenon in a strongly interacting ultracold Fermi gas

H. Tajima, R. Hanai, Yoji Ohashi

Research output: Contribution to journalArticle

Abstract

We investigate magnetic properties of a strongly interacting ultracold Fermi gas. Within the framework of an extended T-matrix approximation, we calculate the spin susceptibility χ in the unitarity limit. We show that effects of pairing fluctuations on this magnetic quantity are quite different in between the normal state and the superfluid phase. In the normal state, pairing fluctuations cause spin-gap phenomenon near the superfluid phase transition temperature Tc, where χ is anomalously suppressed. In the superfluid phase, on the other hand, the ordinary suppression of χ by the BCS energy gap is weakened by pairing fluctuations, because they induce finite density of states inside the gap. Our results indicate that the spin susceptibility is a useful quantity for the study of pairing fluctuations in the BCS-BEC crossover regime of an ultracold Fermi gas.

Original languageEnglish
Article number012019
JournalJournal of Physics: Conference Series
Volume568
DOIs
Publication statusPublished - 2014

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gases
magnetic permeability
crossovers
transition temperature
retarding
magnetic properties
causes
approximation

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Spin-gap phenomenon in a strongly interacting ultracold Fermi gas. / Tajima, H.; Hanai, R.; Ohashi, Yoji.

In: Journal of Physics: Conference Series, Vol. 568, 012019, 2014.

Research output: Contribution to journalArticle

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