English

A study of the dimer-trimer crossover in a driven three-component Fermi gas

Quantum Gases 2026-05-19 v1

Abstract

We develop an Effective Field Theory (EFT) for a system with three distinguishable atomic species and present a variational calculation of the two and three-body binding energies in vacuum and in the presence of a single Fermi sea. Specifically, we consider the case where the interaction between first two atomic species is externally driven so as to produce a (non-universal) closed-channel dimer whose coupling can be controlled independently of all other interactions. We then model the remaining interactions as a contact interaction between the dimer and a third atomic species which forms the medium. We derive analytical expressions for the dimer and trimer binding energies in vacuum and in medium, and in the latter case we predict a crossing between the dimer and trimer branches as a function of the atom-dimer scattering length, analogous to the usual polaron and molecule problem. Furthermore, we show that the position of this crossing can be controlled by varying the atom-atom coupling that results from the external drive and we discuss the implications of these findings.

Keywords

Cite

@article{arxiv.2605.18405,
  title  = {A study of the dimer-trimer crossover in a driven three-component Fermi gas},
  author = {Ronnie Slowinski and Gaël Servignat and Frédéric Chevy and Carlos Lobo},
  journal= {arXiv preprint arXiv:2605.18405},
  year   = {2026}
}
R2 v1 2026-07-22T07:19:09.668Z