Fermions meet two bosons — the heteronuclear Efimov effect revisited

Abstract:

In this article, we revisit the heteronuclear Efimov effect in a Bose-Fermi mixture with large mass difference in the Born-Oppenheimer picture. As a specific example, we consider the combination of bosonic ¹³³Cs and fermionic ⁶Li. In a system consisting of two heavy bosons and one light fermion, the fermion-mediated potential between the two heavy bosons gives rise to an infinite series of three-body bound states. The intraspecies scattering length determines the three-body parameter and the scaling factor between consecutive Efimov states. In a second scenario, we replace the single fermion by an entire Fermi Sea at zero temperature. The emerging interaction potential for the two bosons exhibits long-range oscillations leading to a weakening of the binding and a breakup of the infinite series of Efimov states. In this scenario, the binding energies follow a modified Efimov scaling law incorporating the Fermi momentum. The scaling factor between deeply bound states is governed by the intraspecies interaction, analogous to the Efimov states in vacuum.

B. Tran, M. Rautenberg, M. Gerken, E. Lippi, B. Zhu, J. Ulmanis, M. Drescher, M. Salmhofer, T. Enss, M. Weidemüller, “Fermions meet two bosons—the heteronuclear Efimov effect revisited”, Braz. J. Phys. 51 (2021).

https://link.springer.com/article/10.1007%2Fs13538-020-00811-5

Related to Project: C03