Quantum droplet in a mixture of Rb-Na Bose-Einstein condensates

According to the mean-field theory, an atomic Bose-Einstein condensate (BEC) will collapse when the interaction between atoms is attractive. However, the mixture of two BECs with attractive interspecies interaction can be stabilized by the beyond mean-field Lee-Huang-Yang correction in the format of self-bound quantum droplets. In this talk, I will present our progress in studying the heteronuclear quantum droplet with the double BEC of Rb and Na atoms. With the help of an interspecies Feshbach resonance, we have created double BECs with nearly arbitrary interaction strengths and signs. This should allow us to cover the full phase diagram from two miscible or phase separated condensates, collapsing, and the droplet.