Tunable three-body interactions in driven two-component Bose-Einstein condensates

TL;DR

This paper demonstrates how effective attractive three-body interactions can be engineered in driven two-component Bose-Einstein condensates, with tunable strength via Rabi coupling, affecting the condensate's properties without added losses.

Contribution

It introduces a method to control three-body interactions in BECs through spinor degrees of freedom and Rabi coupling, a novel approach in quantum gas manipulation.

Findings

Three-body interactions significantly influence the condensate's equation of state.

Observation of a downshift in the radial breathing mode frequency.

Radial collapses occur for positive dressed-state scattering lengths.

Abstract

We propose and demonstrate the appearance of an effective attractive three-body interaction in coherently-driven two-component Bose Einstein condensates. It originates from the spinor degree of freedom that is affected by a two-body mean-field shift of the driven transition frequency. Importantly, its strength can be controlled with the Rabi-coupling strength and it does not come with additional losses. In the experiment, the three-body interactions are adjusted to play a predominant role in the equation of state of a cigar-shaped trapped condensate. This is confirmed though two striking observations: a downshift of the radial breathing mode frequency and the radial collapses for positive values of the dressed-state scattering length.