Compact setup for the production of (87)Rb |F = 2, m = + 2〉 Bose-Einstein condensates in a hybrid trap

Rev Sci Instrum. 2016 Aug;87(8):083102. doi: 10.1063/1.4960395.

Abstract

We present a compact experimental apparatus for Bose-Einstein condensation of (87)Rb in the |F = 2, mF = + 2〉 state. A pre-cooled atomic beam of (87)Rb is obtained by using an unbalanced magneto-optical trap, allowing controlled transfer of trapped atoms from the first vacuum chamber to the science chamber. Here, atoms are transferred to a hybrid trap, as produced by overlapping a magnetic quadrupole trap with a far-detuned optical trap with crossed beam configuration, where forced radiofrequency evaporation is realized. The final evaporation leading to Bose-Einstein condensation is then performed by exponentially lowering the optical trap depth. Control and stabilization systems of the optical trap beams are discussed in detail. The setup reliably produces a pure condensate in the |F = 2, mF = + 2〉 state in 50 s, which includes 33 s loading of the science magneto-optical trap and 17 s forced evaporation.