Pairing and radio-frequency spectroscopy in two-dimensional Fermi gases

Abstract

We theoretically study the normal phase properties of strongly interacting two-component Fermi gases in two spatial dimensions. In the limit of weak attraction, we find that the gas can be described in terms of effective polarons. As the attraction between fermions increases, we find a crossover from a gas of non-interacting polarons to a pseudogap regime. We investigate how this crossover is manifested in the radio-frequency (rf) spectroscopy. Our findings qualitatively explain the differences in the recent rf spectroscopy measurements of two-dimensional Fermi gases [Sommer et al., Phys. Rev. Lett. 108, 045302 (2012) and Zhang et al., Phys. Rev. Lett. 108, 235302 (2012)].

arXiv comment11 pages, 9 figures; v2: slightly expanded, typos corrected; v3: published version

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Cited by in corpus (17)

• Quantum fluctuations in the BCS-BEC crossover of two-dimensional Fermi gases
• Pairing effects in the normal phase of a two-dimensional Fermi gas
• Thermal crossover, transition, and coexistence in Fermi polaronic spectroscopies
• Low-dimensional pairing fluctuations and pseudogapped photoemission spectrum in a trapped two-dimensional Fermi gas
• Comparison of strong-coupling theories for a two-dimensional Fermi gas
• BCS-BEC crossover in a quasi-two-dimensional Fermi gas
• Quasi-two-dimensional Fermi gases at finite temperature
• Collective modes of a two-dimensional Fermi gas at finite temperature
• Evolution of Cooper pairs with zero-center-of-mass momentum and their first-order correlation function in a two-dimensional ultracold Fermi gas near the observed Berezinskii-Kosterlitz-Thouless transition
• Pseudogap regime of a strongly interacting two-dimensional Fermi gas with and without confinement-induced effect range of interactions
• Pseudogap phenomena in a two-dimensional ultracold Fermi gas near the Berezinskii-Kosterlitz-Thouless transition
• Low-Dimensional Fluctuations and Pseudogap in Gaudin-Yang Fermi Gases
• Pseudogap regime of a two-dimensional uniform Fermi gas
• Momentum distribution of Cooper-pairs and strong-coupling effects in a two-dimensional Fermi gas near the Berezinskii-Kosterlitz-Thouless transition
• Peaks and widths of radio-frequency spectra: An analysis of the phase diagram of ultra-cold Fermi gases
• Spectral intensity distribution of trapped fermions
• Tunneling spectra of unconventional quasi-two-dimensional superconductors