Bose-Einstein condensation of 85Rb by direct evaporation in an optical dipole trap

TL;DR

This paper presents a straightforward method to produce Bose-Einstein condensates of 85Rb using direct evaporation in an optical dipole trap, allowing precise control of interactions via a Feshbach resonance.

Contribution

The study introduces a simple, controllable approach for creating 85Rb BECs through direct evaporation in an optical trap with independent frequency and magnetic field control.

Findings

Achieved nearly pure condensates of 4×10^4 atoms.

Demonstrated tunability of atomic interactions near 155 G Feshbach resonance.

Enabled full control of trap parameters and collision dynamics.

Abstract

We report a simple method for the creation of Bose-Einstein condensates of $^{85}$Rb by direct evaporation in a crossed optical dipole trap. The independent control of the trap frequencies and magnetic bias field afforded by the trapping scheme permits full control of the trapped atomic sample, enabling the collision parameters to be easily manipulated to achieve efficient evaporation in the vicinity of the 155 G Feshbach resonance. We produce nearly pure condensates of up to $4\times10^4$ atoms and demonstrate the tunable nature of the atomic interactions.