This thesis demonstrates a new cooling and trap loading technique for molecules, leading to trapping of calcium monofluoride (CaF). Two key principles developed and used are a very slow molecular beam and irreversible loading of a magnetic trap via optical pumping. The cooling of molecules occurs inside a cryogenic buffer-gas cell, where collisions between the molecules and cold, inert buffer gas cool the initially hot molecules.;Cold molecules emitted out the cell through an exit aperture enter another slowing cell with a piece of mesh on the final exit aperture. Such a two-stage cell provides slow monohydride (CaH) molecules with a moving velocity of 60 m/s and a flux of 109 molecules/pulse.;This technique is completely general, and is applied to produce slow beams of atomic potassium and CaF. We direct a slow CaF beam with vf N=1, with a trap lifetime exceeding 500 ms. Trajectory simulations are developed to optimize the loading process and simulate the loss of trapped molecules. The attained trap lifetime is limited by elastic collisions with the background 3He gas at a density of 5x10 10 cm-3. Using this new loading method, we also realized trapping of CaF (N=0) and CaH (N=0). This work provides the platform for future work. We plan to co-load CaH molecules with Li atoms to study cold collisions and cold controlled chemistry inside the trap, which may shed the light on further cooling of molecules using Li as the coolant. Laser cooling of trapped CaF (N=1) may be feasible inside the trap. Magnetic trapping of chemically diverse molecules without closed cycling transitions, including triatomic molecules, may be realized with the scattering of only a few photons.
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机译：本文证明了一种新的分子冷却和捕集负载技术，可导致捕获单氟化钙（CaF）。开发和使用的两个关键原理是非常慢的分子束和通过光泵浦对磁阱的不可逆加载。分子的冷却发生在低温缓冲气体池中，其中分子与冷的惰性缓冲气体之间的碰撞冷却了最初的热分子。通过出口孔从池中喷出的冷分子进入另一个带网孔的减速池中在最后的出口孔上。这样的两级电池可提供慢速一氢化物（CaH）分子，其移动速度为60 m / s，通量为109分子/脉冲。;该技术是完全通用的，可用于产生原子钾和CaF的慢束。我们以vf N = 1引导慢速CaF光束，陷阱寿命超过500毫秒。进行了轨迹模拟，以优化加载过程并模拟被困分子的损失。与背景3He气体以5x10 10 cm-3的密度发生弹性碰撞会限制所达到的捕集阱寿命。使用这种新的加载方法，我们还实现了CaF（N = 0）和CaH（N = 0）的捕获。这项工作为将来的工作提供了平台。我们计划将CaH分子与Li原子共同负载，以研究阱中的冷碰撞和冷控制化学反应，这可能会为使用Li作为冷却剂的分子进一步冷却提供启示。在阱内部可以对捕获的CaF（N = 1）进行激光冷却。可以通过仅几个光子的散射来实现化学封闭的，无化学变化的分子（包括三原子分子）的无封闭循环跃迁的磁性捕获。
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