Development Of A Miniaturized Optical Frequency Standard Based On Single Calcium Ion

With the advent of the era of optical frequency standard, developing a miniaturized and practical optical frequency standard to meet the growing needs has become one of the important issues in the field of time and frequency standard. In this article, we chose a single trapped calcium ion as the physical reference and carried out a series of research on miniaturized optical frequency standard. The topics covered by this thesis are categorized as follows:1. A scheme of miniaturized optical frequency standards based on modular unit and overall integration was proposed, and a detailed design of miniaturized optical frequency standard based on single calcium ion was carried out. According to this scheme, all the hardware could be contained in the range of1200x900x500mm3, with the volume about0.54m3.2. Through the method of finite element analysis, a guide for the design and construction of a miniature ring-endcap ion trap was presented. Moreover, an optimized combination of rring/rendcap=0.5and z0=r0within the range of r0=0.7±0.2mm was obtained. This improvement made it closer to an ideal hyperboloidal trap to confine a single ion tightly with weaker micromotion.3. A simple423nm frequency doubled laser was developed. Using this laser, calcium ion was prroduced by photo ionization with the great advantages of clean and high-efficiency, which were critical in reducing the excess-micromotion and increasing the trapped time of single ion. With this method, a single calcium ion could be stay in the trap for17days at longest.4. Two kinds of three-in-one method of laser frequency stabilization based on transfer cavity and ULE cavity were proposed, and they were carried out respectively on397nm,866nm and854nm lasers with the frequency drifts were controlled at MHz level per day. Its advantages of integration and high-efficiency could satisfy the requirement of miniaturized optical frequency standards well.5. A miniaturized optical frequency standard based on single calcium ion was developed. The linewidth of729nm clock laser was about4Hz. With this probing laser, a linewidth about80Hz was obtained from the component(△mj=0) of Zeeman spectrum. Finally, this miniaturized optical frequency standard based on single calcium ion was locked for2hours successfully.