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arXiv · 1807.10208

Time-resolved observation of competing attractive and repulsive short-range correlations in strongly interacting Fermi gases

A. Amico·F. Scazza·G. Valtolina·P. E. S. Tavares·W. Ketterle·M. Inguscio·G. Roati·M. Zaccanti
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Abstract

We exploit a time-resolved pump-probe spectroscopic technique to study the out-of-equilibrium dynamics of an ultracold two-component Fermi gas, selectively quenched to strong repulsion along the upper branch of a broad Feshbach resonance. For critical interactions, we find the rapid growth of short-range anti-correlations between repulsive fermions to initially overcome concurrent pairing processes. At longer evolution times, these two competing mechanisms appear to macroscopically coexist in a short-range correlated state of fermions and pairs, unforeseen thus far. Our work provides fundamental insights into the fate of a repulsive Fermi gas, and offers new perspectives towards the exploration of complex dynamical regimes of fermionic matter.

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A. Amico, F. Scazza, G. Valtolina, P. E. S. Tavares, W. Ketterle, M. Inguscio, G. Roati, M. Zaccanti. 2018-12-26. Time-resolved observation of competing attractive and repulsive short-range correlations in strongly interacting Fermi gases. https://doi.org/10.1103/physrevlett.121.253602

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