Optics Express

Two-stage crossed beam cooling with ^6Li and ^133Cs atoms in microgravity

Tian Luan, Hepeng Yao, Lu Wang, Chen Li, Shifeng Yang, Xuzong Chen, Zhaoyuan Ma

Published Apr 22, 2015• 16 citations

Abstract

Applying the direct simulation Monte Carlo (DSMC) method developed for ultracold Bose-Fermi mixture gases research, we study the sympathetic cooling process of 6Li and 133Cs atoms in a crossed optical dipole trap. The obstacles to producing 6Li Fermi degenerate gas via direct sympathetic cooling with 133Cs are also analyzed, by which we find that the side-effect of the gravity is one of the main obstacles. Based on the dynamic nature of 6Li and 133Cs atoms, we suggest a two-stage cooling process with two pairs of crossed beams in microgravity environment. According to our simulations, the temperature of 6Li atoms can be cooled to T = 29.5 pK and T/TF = 0.59 with several thousand atoms, which propose a novel way to get ultracold fermion atoms with quantum degeneracy near pico-Kelvin.

DOI: 10.1364/oe.23.011378

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