Single-Particle Momentum Distribution of an Efimov trimer

Abstract

Experimental progress in the study of strongly interacting ultracold atoms has recently allowed the observation of Efimov trimers. We study theoretically a non-conventional observable for these trimer states, that may be accessed experimentally, the momentum distribution n(k) of the constitutive bosonic particles. The large momentum part of the distribution is particularly intriguing: In addition to the expected 1/k^4 tail associated to contact interactions, it exhibits a subleading tail 1/k^5 which is a hall-mark of Efimov physics and leads to a breakdown of a previously proposed expression of the energy as a functional of the momentum distribution.

This is a subpart of the (too long to be published) work arXiv:1001.0774. This subpart has 11 pages and 2 figures. Revised version correcting minor errors