Atom loss from the $^{85}$Rb Bose-Einstein condensate by a Feshbach resonance

TL;DR

This paper investigates atom loss in a $^{85}$Rb Bose-Einstein condensate near a Feshbach resonance, revealing quantum many-body effects that increase losses and produce entangled atom pairs, aligning better with experimental data.

Contribution

It introduces a generalized parametric approximation that incorporates quantum effects, improving predictions over mean-field theories for atom loss near Feshbach resonances.

Findings

Quantum many-body effects significantly increase atom loss.

The method aligns better with experimental observations.

Entangled atom pairs are produced during loss processes.

Abstract

Loss of atoms from a $^{85}$Rb condensate on passage through a Feshbach resonance is analyzed using the generalized parametric approximation that takes into account quantum many-body effects. These effects lead to a substantial increase of the losses. A better agreement with experiments is achieved, compared to predictions of mean-field theories. The method provides much insight into the quantum effects involved, and on the nature of entangled atom pairs produced by the loss.