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arXiv · 1207.1163

Two-dimensional pseudogap effects of an ultracold Fermi gas in the BCS-BEC crossover region

Ryota Watanabe·Shunji Tsuchiya·Yoji Ohashi
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Abstract

We investigate pseudogap phenomena originating from pairing fluctuations in the BCS-BEC crossover regime of a two-dimensional Fermi gas in a harmonic trap. Including pairing fluctuations within a $T$-matrix theory and effects of a trap within the local density approximation, we calculate the local density of states (LDOS) at the superfluid phase transition temperature $T_{\rm c}$. In the weak-coupling regime, we show that the pseudogap already appears in LDOS around the trap center. The spatial region where the pseudogap can be seen in LDOS becomes wider for a strong pairing interaction. We also discuss how the pseudogap affects the spectrum of the photoemission-type experiment developed by JILA group.

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Ryota Watanabe, Shunji Tsuchiya, Yoji Ohashi. 2012-07-05. Two-dimensional pseudogap effects of an ultracold Fermi gas in the BCS-BEC crossover region. https://doi.org/10.1007/s10909-012-0691-7

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