Low-dimensional pairing fluctuations and pseudogapped photoemission spectrum in a trapped two-dimensional Fermi gas

Ryota Watanabe, Shunji Tsuchiya, Yoji Ohashi

Research output: Contribution to journalArticle

21 Citations (Scopus)

Abstract

We investigate strong-coupling properties of a trapped two-dimensional normal Fermi gas. Within the framework of a combined T-matrix theory with the local density approximation, we calculate the local density of states, as well as the photoemission spectrum, to see how two-dimensional pairing fluctuations affect these single-particle quantities. In the BCS (Bardeen-Cooper-Schrieffer)- BEC (Bose-Einstein condensation) crossover region, we show that the local density of states exhibits a dip structure in the trap center, which is more remarkable than the three-dimensional case. This pseudogap phenomenon is found to naturally lead to a double-peak structure in the photoemission spectrum. The peak-to-peak energy of the spectrum at p=0 agrees well with a recent experiment on a two-dimensional 40K Fermi gas. Since pairing fluctuations are sensitive to the dimensionality of a system, our results would be useful for the study of many-body physics in the BCS-BEC crossover regime of a two-dimensional Fermi gas.

Original languageEnglish
Article number013637
JournalPhysical Review A - Atomic, Molecular, and Optical Physics
Volume88
Issue number1
DOIs
Publication statusPublished - 2013 Jul 29

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photoelectric emission
crossovers
condensation
gases
matrix theory
traps
physics
approximation
energy

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics

Cite this

Low-dimensional pairing fluctuations and pseudogapped photoemission spectrum in a trapped two-dimensional Fermi gas. / Watanabe, Ryota; Tsuchiya, Shunji; Ohashi, Yoji.

In: Physical Review A - Atomic, Molecular, and Optical Physics, Vol. 88, No. 1, 013637, 29.07.2013.

Research output: Contribution to journalArticle

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