Norrgard E B, McCarron D J, Steinecker M H, Tarbutt M R, DeMille D
Department of Physics, Yale University, P.O. Box 208120, New Haven, Connecticut 06520, USA.
Centre for Cold Matter, Blackett Laboratory, Imperial College London, Prince Consort Road, London SW7 2AZ, United Kingdom.
Phys Rev Lett. 2016 Feb 12;116(6):063004. doi: 10.1103/PhysRevLett.116.063004. Epub 2016 Feb 10.
We demonstrate a scheme for magneto-optically trapping strontium monofluoride (SrF) molecules at temperatures one order of magnitude lower and phase space densities 3 orders of magnitude higher than obtained previously with laser-cooled molecules. In our trap, optical dark states are destabilized by rapidly and synchronously reversing the trapping laser polarizations and the applied magnetic field gradient. The number of molecules and trap lifetime are also significantly improved from previous work by loading the trap with high laser power and then reducing the power for long-term trapping. With this procedure, temperatures as low as 400 μK are achieved.
我们展示了一种用于磁光捕获一氟化锶（SrF）分子的方案，该方案能在比之前激光冷却分子所达到的温度低一个数量级、相空间密度高3个数量级的条件下实现捕获。在我们的阱中，通过快速且同步地反转捕获激光偏振和所施加的磁场梯度，使光学暗态失稳。通过以高激光功率加载阱然后降低功率以进行长期捕获，分子数量和阱寿命也比之前的工作有了显著提高。通过此程序，可实现低至400 μK的温度。
