Luan Tian, Yao Hepeng, Wang Lu, Li Chen, Yang Shifeng, Chen Xuzong, Ma Zhaoyuan
Opt Express. 2015 May 4;23(9):11378-87. doi: 10.1364/OE.23.011378.
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.
应用为超冷玻色 - 费米混合气体研究开发的直接模拟蒙特卡罗（DSMC）方法，我们研究了交叉光学偶极阱中6Li和133Cs原子的交感冷却过程。还分析了通过与133Cs直接交感冷却产生6Li费米简并气体的障碍，由此我们发现重力的副作用是主要障碍之一。基于6Li和133Cs原子的动力学性质，我们提出了在微重力环境下用两对交叉光束进行两阶段冷却的过程。根据我们的模拟，几千个6Li原子的温度可以冷却到T = 29.5 pK且T/TF = 0.59，这为获得接近皮开尔文量子简并的超冷费米子原子提出了一种新方法。
