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arXiv · 2004.12759

An impurity immersed in a double Fermi Sea

Ragheed Alhyder·Xavier Leyronas·Frederic Chevy
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Abstract

We present a variational calculation of the energy of an impurity immersed a double Fermi sea of non-interacting Fermions. We show that in the strong-coupling regime, the system undergoes a first order transition between polaronic and trimer states. Our result suggests that the smooth crossover predicted in previous literature for a superfluid background is the consequence of Cooper pairing and is absent in a normal system.

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Ragheed Alhyder, Xavier Leyronas, Frederic Chevy. 2020-04-27. An impurity immersed in a double Fermi Sea. https://doi.org/10.1103/physreva.102.033322

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