Spectrum and Dynamics of the BCS-BEC crossover from a few-body perspective

Abstract

The spectrum of two spin-up and two spin-down fermions in a trap is calculated using a correlated gaussian basis throughout the range of the BCS-BEC crossover. These accurate calculations provide a few-body solution to the crossover problem. This solution is used to study the time-evolution of the system as the scattering length is changed, mimicking experiments with Fermi gases near Fano-Feshbach resonances. The structure of avoiding crossings in the spectrum allow us to understand the dynamics of the system as a sequence of Landau-Zener transitions. Finally, we propose a ramping scheme to study atom-molecule coherence.

arXiv comment4 pages, final version to appear in PRL

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Cited by in corpus (53)

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• Small mass- and trap-imbalanced two-component Fermi systems
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• Adiabaticity and diabaticity in strong-field ionization
• Universal few-body physics in a harmonic trap
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• Stability of Inhomogeneous Multi-Component Fermi Gases
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• Efimov physics implications at $p$-wave fermionic unitarity
• Perspectives on few-body cluster structures in exotic nuclei
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• Few-body ultracold reactions in a Bose-Fermi mixture
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• When does a Fermi puddle become a Fermi sea? Emergence of pairing in two-dimensional trapped mesoscopic Fermi gases