Two-Species Mixture of Quantum Degenerate Bose and Fermi Gases

Abstract

We have produced a macroscopic quantum system in which a ${}^{6}\mathrm{Li}$ Fermi sea coexists with a large and stable ${}^{23}\mathrm{Na}$ Bose-Einstein condensate. This was accomplished using interspecies sympathetic cooling of fermionic ${}^{6}\mathrm{Li}$ in a thermal bath of bosonic ${}^{23}\mathrm{Na}$. The system features rapid thermalization and long lifetimes.