Bose-Einstein condensation of rubidium atoms

A setup for preparing the Bose-Einstein condensate of rubidium atoms has been built. The condensate consists of $10^5$–$10^6$ $^{87}$Rb atoms in the hyperfine state $F_g=2$ of the ground electronic state. Three key indications of condensation – a sharp increase in the phase-space density of atoms, the threshold emergence of two fractions in the cloud, and anisotropic expansion of the condensate – have been observed.