Effects of 3-body resonances in ultracold bose gases

Anindya Biswas

José Paulo D'Incao, Javier von Stecher, Chris H. Greene

Brett D. Esry, Hiroya Suno, Chris H. Greene

Three-body recombination can play an important role in experiments on ultracold atomic gases because it can produce significant atom loss. Such losses have been seen in Bose-Einstein condensates, but have been thought to play little role for degenerate Fermi gases. We show that under some circumstances, three-body recombination can be just as large in fermi systems as in bose systems. In particular, when there is a two-body resonance near threshold — as is often the case experimentally — the threshold suppression due to the Pauli principle no longer applies. 1

José Paulo D'Incao

R. Combescot

We propose a coherent framework allowing one to treat many-body effects in dense ultracold Fermi gases in the presence of a Feshbach resonance. We show that the simple effect of Pauli exclusion induces a strong modification of the basic scattering properties. In particular, this washes out the Feshbach resonance and provides a natural explanation for recent experimental findings.

James R. Macdonald Labs