Pseudogap in fermionic density of states in the BCS-BEC crossover of atomic fermi gases

S. Tsuchiya, R. Watanabe, Yoji Ohashi

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

We study pseudogap behaviors of ultracold Fermi gases in the BCS-BEC crossover region. We calculate the density of states (DOS), as well as the single-particle spectral weight, above the superfluid transition temperature T c including pairing fluctuations within a T-matrix approximation. We find that DOS exhibits a pseudogap structure in the BCS-BEC crossover region, which is most remarkable near the unitarity limit. We determine the pseudogap temperature T * at which the pseudogap structure in DOS disappears. We also introduce another temperature T** at which the BCS-like double-peak structure disappears in the spectral weight. While one finds T* >T** in the BCS regime, T ** becomes higher than T* in the crossover and BEC regime. We also determine the pseudogap region in the phase diagram in terms of temperature and pairing interaction.

Original languageEnglish
Pages (from-to)29-35
Number of pages7
JournalJournal of Low Temperature Physics
Volume158
Issue number1-2
DOIs
Publication statusPublished - 2010 Jan

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crossovers
Gases
gases
Temperature
Superconducting transition temperature
Phase diagrams
temperature
transition temperature
phase diagrams
approximation
interactions

Keywords

  • Atomic Fermi gas
  • BCS-BEC crossover
  • Pseudogap

ASJC Scopus subject areas

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

Cite this

Pseudogap in fermionic density of states in the BCS-BEC crossover of atomic fermi gases. / Tsuchiya, S.; Watanabe, R.; Ohashi, Yoji.

In: Journal of Low Temperature Physics, Vol. 158, No. 1-2, 01.2010, p. 29-35.

Research output: Contribution to journalArticle

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