Experimental study of matter-wave four-wave mixing in $^{39}$K Bose-Einstein condensates with tunable interaction

TL;DR

This study experimentally explores matter-wave four-wave mixing in $^{39}$K Bose-Einstein condensates, demonstrating how tunable interactions influence FWM yield and identifying optimal conditions near phase transition regions.

Contribution

It provides new experimental insights into how interaction tuning affects matter-wave FWM in different geometric and phase regimes.

Findings

FWM yield increases with larger scattering length in single-spin configuration

Maximum FWM yield occurs near the phase transition between gas and droplet states

Results can optimize matter-wave amplification and entangled atom pair production

Abstract

We experimentally investigate four-wave mixing (FWM) of matter waves in two geometric configurations in $^{39}$K Bose-Einstein condensates with the atomic interaction tuned via Feshbach resonances. For one configuration with the single-spin component, the FWM yield increases with a larger scattering length. For the two-spin component configuration, we specifically investigate FWM in both the droplet and gas parameter regimes. We find that the FWM yield reaches its maximum near the critical parameter region between the gas and droplet phases. Our research can help to optimize the FWM yield for matter-wave amplification and entangled atom pair generation, making it conducive to applications in quantum information processing and precision measurement.