Magnetic properties and strong-coupling corrections in an ultracold fermi gas with population imbalance

T. Kashimura, R. Watanabe, Yoji Ohashi

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

We investigate magnetic properties of an ultracold Fermi gas with population imbalance. In the presence of population imbalance, the strong-coupling theory developed by Nozières and Schmitt-Rink (which is frequently referred to as the NSR theory, or Gaussian fluctuation theory) is known to give unphysical results in the BCS-BEC crossover region. We point out that this problem comes from how to treat pseudogap effects originating from pairing fluctuations and many-body corrections to the spin susceptibility. We also clarify how to overcome this problem by including higher order fluctuations beyond the ordinary T -matrix approximation. Calculated spin susceptibility based on our extended T -matrix approximation agrees well with the recent experiment on a 6Li Fermi gas.

Original languageEnglish
Pages (from-to)355-361
Number of pages7
JournalJournal of Low Temperature Physics
Volume171
Issue number3-4
DOIs
Publication statusPublished - 2013

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Magnetic properties
Gases
magnetic properties
magnetic permeability
fluctuation theory
approximation
gases
crossovers
Experiments

Keywords

  • Population imbalance
  • Strong-coupling effects
  • Superfluidity

ASJC Scopus subject areas

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

Cite this

Magnetic properties and strong-coupling corrections in an ultracold fermi gas with population imbalance. / Kashimura, T.; Watanabe, R.; Ohashi, Yoji.

In: Journal of Low Temperature Physics, Vol. 171, No. 3-4, 2013, p. 355-361.

Research output: Contribution to journalArticle

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