Rb原子的激光冷却与囚禁

【作者】 王谨；

【导师】 詹明生；

【作者基本信息】 中国科学院研究生院（安徽光学精密机械研究所） ， 光学， 1999， 博士

【摘要】 中性原子的激光冷却与囚禁是原子物理学中一个崭新的研究领域,因其具有深远的物理意义和广阔的应用前景而引起了物理学家的普遍关注。本学位论文围绕Rb原子的激光冷却与囚禁,报道了以下几个方面的工作: 综述了激光冷却与囚禁原子、分子的研究历史及发展过程,介绍了国内外的研究现状和最新成果,展望了原子的激光冷却与囚禁技术的应用前景。叙述了激光冷却与囚禁中性原子的相关原理,介绍了一些激光冷却与囚禁中性原子的常用实验方法,重点介绍了磁光阱的工作原理和实验方案。建立了一套激光囚禁Rb原子的实验装置,描述了Rb气室、Rb样品源、磁场线圈的制作和高真空条件下样品的装载方法。叙述了实验中光学系统、激光器系统的组成和信号监视的手段。在熟悉光栅外腔稳频二极管激光器的性能的基础上,制作了温度控制和稳频反馈电路,用无多谱勒饱和吸收光谱的方法实现了二极管激光器的稳频,使激光器的有效线宽小于1MHz,同时用声光调制的办法实现了激光的频率红移,解决了激光冷却与囚禁原子中的一个关键问题。详细介绍了Rb原子饱和吸收光谱的获得和激光器的稳频、移频的步骤。实现了Rb原子的激光冷却与囚禁。用CCD观察到了Rb原子激光囚禁的稳定信号,获得了几种不同条件下Rb原子激光囚禁的照片,初步研究了囚禁信号对激光频率、磁场梯度和真空度等实验条件的依赖关系。已基本完成实验装置的改进,提出了后续工作设想,计划在改进后的实验装置上开展激光囚禁原子的高分辨率光谱的研究。更多还原

【Abstract】 Laser cooling and trapping of atoms is a new area in atomic physics, physicists pay more attention to it due to its physical significance and the possibility of wide application in the future. In this thesis, a realization of laser cooling and trapping of rubidium atoms is reported. Firstly, the history and development of laser cooling and trapping of neutral atoms and molecules is reviewed. Present study status and future development is prospected. Principle of laser cooling and trapping of atoms as well as techniques used in laser cooling and trapping are described. An experimental setup for laser cooling and trapping of rubidium atoms was established. The details of the apparatus including Rb cell, Rb source, magnetic field coils,the optical system, lasers and the monitoring of signal are then presented. The laser frequency stabilization is a key technique in the realization of laser cooling and trapping. To do this, temperature control circuit, a feedback circuit and Doppler-free saturated absorption spectroscopy method were used. The commercial diode laser was then stabilized to a linewidth of less than 1 MHz. The laser frequency was further shifted and scanned by an acousto-optical modulator. Laser cooling and trapping of Rb atoms was realized. The steady signal of laser trapped Rb atoms was observed by CCD camera. Captured pictures of trapped Rb atoms vary as experimental conditions, such as laser frequency, gradient of magnetic field, and the Rb vapor. Lastly the extension of the work is planned. Primary experimental preparation and scheme to do the high-resolution spectroscopy using the trapped Rb atoms are included.更多还原