中国激光, 2011, 38 (7): 0708004, 网络出版: 2011-05-31
刀口法测量铬原子激光冷却温度
Thermometry of Cr Laser Cooling via Knife-Edge
测量 原子光刻 激光多普勒冷却 刀口测温法 角分布 横向温度 measurement atom lithography laser Doppler cooling knife-edge thermometry angular distribution transverse temperature
摘要
介绍了刀口法测温原理。在自主研制的铬原子光刻系统上,利用稳定到52Cr的7S3→7P04跃迁上的真空波长为425.5 nm的激光,对高温原子炉喷射的铬原子束进行了一维多普勒冷却准直。设计搭建了刀口法测温实验装置,对激光多普勒冷却准直效果进行了定量评价。在激光功率为45 mW,失谐量为-2.5 MHz,光斑大小为1 mm×20 mm的条件下,观察到了明显的冷却现象。在此基础上采用刀口法测温,测得激光冷却后铬原子束角分布的半峰全宽为(0.616±0.007) mrad,横向温度为(418±10) μK。这些结果为优化调整铬原子束激光冷却准直实验提供了依据。
Abstract
The principle of knife-edge thermometry is introduced. A chromium beam which is jetted from high temperature atomic crucible is collimated by one-dimensional laser Doppler cooling on self-designed system of chromium atom lithography. The laser wavelength in vacuum is 425.5 nm, corresponding to 7S3→7P04 transition of 52Cr. The setup of knife-edge thermometry is designed and built to quantify the effect of the chromium beam collimation by laser cooling. The obvious cooling phenomenon is observed with power of 45 mW, spot size of 1 mm×20 mm and detuning of -2.5 MHz. Then, based on it, the knife-edge measurement is carried out. The results show that the full-width at half-maximum (FWHM) of chromium beam angular distribution is (0.616±0.007) mrad and the transverse temperature is (418±10) μK by laser cooling. The results provide a basis for optimizing the chromium beam collimation by laser cooling.
焦晓光, 殷聪, 石春英, 钱进. 刀口法测量铬原子激光冷却温度[J]. 中国激光, 2011, 38(7): 0708004. Jiao Xiaoguang, Yin Cong, Shi Chunying, Qian Jin. Thermometry of Cr Laser Cooling via Knife-Edge[J]. Chinese Journal of Lasers, 2011, 38(7): 0708004.