Three-body bound states of two bosonic impurities immersed in a Fermi sea in 2D

• Main Author: Bellotti, F. F.
• Publication Date: 2016
• Other Authors: Frederico, T., Yamashita, M. T. [UNESP], Fedorov, D. V., Jensen, A. S., Zinner, N. T.
• Format: Article
• Language: eng
• Source: Repositório Institucional da UNESP
• Download full: http://dx.doi.org/10.1088/1367-2630/18/4/043023; http://hdl.handle.net/11449/172915
• topic: cold atoms; impurity physics; quantum bound states

We consider two identical impurities immersed in a Fermi sea for a broad range of masses and for both interacting and non-interacting impurities. The interaction between the particles is described through attractive zero-range potentials and the problem is solved in momentum space. The two impurities can attach to a fermion from the sea and form three-body bound states. The energy of these states increase as function of the Fermi momentum kF, leading to three-body bound states below the Fermi energy. The fate of the states depends highly on two- and three-body thresholds and we find evidence of medium-induced Borromean-like states in 2D. The corrections due to particle-hole fluctuations in the Fermi sea are considered in the three-body calculations and we show that in spite of the fact that they strongly affect both the two- and three-body systems, the correction to the point at which the three-body states cease to exist is small.