Prospect for BEC in a cesium gas: one-dimensional evaporative cooling in a hybrid magnetic and optical trap

Abstract

Bose-Einstein condensation (BEC) in a atomic cesium gas prepared in a “low field seeker” Zeeman sublevel and confined in a magnetic trap has been thwarted by a high cross-section of inelastic spin-flip collisions. A recent experiment [1] succeeded in reaching BEC for cesium atoms using all optical methods and tuning the scattering length. We will discuss a hybrid magnetic and optical trap for cesium atoms in the true hyperfine ground state, the “high field seeker” Zeeman sublevel, F = mF = 3. Although this trap allows only one-dimensional (1D) evaporative cooling, we show that a route towards BEC with such a trap should be possible. We present simulations of 1D evaporative cooling, which shows that a high phase space density (PSD) of 0.1 could be reached in less than 10 seconds.