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arXiv · 1105.1459

Theory of Photoemission-type Experiment in the BCS-BEC Crossover Regime of a Superfluid Fermi Gas

Ryota Watanabe·Shunji Tsuchiya·Yoji Ohashi
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Abstract

We theoretically investigate the recent photoemission-type experiment on $^{40}$K Fermi gases done by JILA group. Including pairing fluctuations within a strong-coupling $T$-matrix theory, as well as effects of a harmonic trap within the local density approximation, we calculate photoemission spectra in the BCS (Bardeen-Cooper-Schrieffer)-BEC (Bose-Einstein condensation) crossover region. We show that the energy resolution of the current photoemission experiment is enough to detect the pseudogap phenomenon. We also show how the pseudogap in single-particle excitations continuously changes into the superfluid gap, as one decreases the temperature below the superfluid phase transition temperature. Our results would be useful for the study of single-particle properties of ultracold Fermi gases in the BCS-BEC crossover.

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Ryota Watanabe, Shunji Tsuchiya, Yoji Ohashi. 2011-05-07. Theory of Photoemission-type Experiment in the BCS-BEC Crossover Regime of a Superfluid Fermi Gas. https://doi.org/10.1109/isas.2011.5960915

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