本實驗報告了我們以磁光陷阱捕捉的方法鉀41原子團的過程。我們捕捉了10^6 個原子，並測得其原子團密度約為10^-9 cm^-3。因為這是我們第一次補捉到鉀41原子團，所以我們對其特性做了一些量測。我們量測了磁場梯度，雷射強度，trapping 雷射和repumping 雷射強度比例對於原子數的關係。另外，我們嘗試了吸收影像法來得到比螢光法更精確的原子數及原子團密度。最後，是我們一個仍在進行中的實驗項目 : 超冷碰撞。我們將從中探討鉀41與銣85原子團碰撞的關係，希望能從中獲得關於這兩種異核原子碰撞的資訊。

We report on trapping of bosonic 41K atoms in a magneto-optical trap. Typically
106 atoms are loaded at a density of 109 cm􀀀3. Since this was the _rst time we
trapped 41K atoms in our experiment, some characteristic measurements were needed.
Dependence of trapping atom numbers due to the magnetic _eld gradient, total cooling
laser power, power ratio of trapping and repumping beam, and the red detuning below
F'= 3 state were measured and compared in our results. We also try to estimate our
trapped atom numbers and densities in a more precise way by absorption image.
In the last part, the event we are undergoing is the heteronuclear atomic collisions
between 41K and 85Rb at temperature about few hundred micro-Kelvin.

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