本實驗研究為從磁光陷阱載入銫原子到光偶極阱。實驗上，我們利用高功率雷射(Nd:YAG 雷射，波長為1064nm，20W)為光源，聚焦光腰約為18μm在已建構好的磁光陷阱系統中，將原子載入其中。利用同軸的共振頻率的D2光來調整光偶極阱的設置，可以從及時的CCD影像系統觀測到在磁光陷阱原子團中有一較亮細細的銫原子群，即為光偶極阱。然後利用另外的成像系統來探測光偶極阱，我們使用吸收法來偵測光偶極阱。為了要得到較清晰的影像，我們量測成像系統受到磁光陷阱原子團螢光的影響、偵測光作用時間、原子團擴散離開偵測晶片的時間、影像背景的扣除等。在此系統下的磁光陷阱的原子數約為1.8×107個、密度約 2.0×1010個/ cm3、溫度約為200μK。從此磁光陷阱載入到的光偶極阱的原子數約為1.1×105個、密度約 6×1010個/cm3、生命期從約150ms到360ms。其光偶極阱影像的長度約1.3mm，寬度約為50μm，溫度從約250μK到560μK。

We have successfully loaded an optical dipole trap from a magneto-optical trap. In this experiment, high power laser (Nd:YAG laser, 1064nm, 20W) has been used as a laser source of dipole trap. YAG laser beam focuses on the MOT to load atoms into optical dipole trap and the focus beam waist is about 18μm. A Cs D2 line F=4 to F=5 on resonance laser beam has been applied for adjusting the focus of YAG laser by making the tow laser beams coaxial in the same propagating way. The fluorescence of optical dipole trap can be seen from CCD image system while keeping MOT on. Therefore, we utilize another image system to detect optical dipole trap. The way of observing optical dipole trap is to probe Cs D2 line F=4 to F=5 on resonance laser beam and the image would be recorded by digital CCD, which is called absorption image. To get the image more clearly, we optimize the image system by measuring probe time, eliminating the effect of MOT fluorescence on the image, removing the background of image, and so on. In the system, the atom number of MOT is about 1.8×107 , a MOT temperature of 200μK, and a density of 2.0×1010 atoms/cm3. The number of atoms in optical dipole trap is about 1.1×105 and the density is 6×1010 atoms/cm3. The length and width of optical dipole trap is about 1.3mm and 50μm, the life time of optical dipole trap ranging between 150ms to 360ms, and the temperature of FORT is from 250μK to 560μK.

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