# Few-to-many particle crossover of pair excitations in a superfluid

@inproceedings{Resare2022FewtomanyPC, title={Few-to-many particle crossover of pair excitations in a superfluid}, author={Fabian Resare and Johannes S. Hofmann}, year={2022} }

Motivated by recent advances in the creation of few-body atomic Fermi gases with attractive interactions, we study theoretically the few-to-many particle crossover of pair excitations, which for large particle numbers evolve into modes describing amplitude ﬂuctuations of the superﬂuid order parameter (the “Higgs” modes). Our analysis is based on a Richardson-type pairing model that captures interactions between time-reversed fermion pairs. The model is integrable, which allows a systematic…

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