A double species $^{23}$Na and $^{87}$Rb Bose-Einstein condensate with tunable miscibility via an interspecies Feshbach resonance

TL;DR

This paper reports the creation of a dual-species Bose-Einstein condensate of sodium and rubidium atoms with tunable interspecies interactions, enabling the study of phase transitions between miscible and immiscible superfluid mixtures.

Contribution

The work demonstrates the realization of a stable dual-species BEC with tunable interactions using a Feshbach resonance, providing a new platform for exploring inter-species interaction effects.

Findings

Successfully created dual-species BEC of $^{23}$Na and $^{87}$Rb

Achieved tunable interspecies interactions via Feshbach resonance

Observed the phase transition between miscible and immiscible states

Abstract

We have realized a dual-species Bose-Einstein condensate (BEC) of $^{23}$Na and $^{87}$Rb atoms and observed their immiscibility. Because of the favorable background intra- and inter-species scattering lengths, stable condensates can be obtained via efficient evaporative cooling and sympathetic cooling without the need for fine tuning of the interactions. Our system thus provides a clean platform for studying inter-species interactions driven effects in superfluid mixtures. With a Feshbach resonance, we have successfully created double BECs with largely tunable inter-species interactions and studied the miscible-immiscible phase transition.