脉冲微波式氢原子钟的研究进展

摘要

在传统被动型氢原子钟基础上,利用复杂可编程逻辑器件( CPLD)控制数字衰减器产生两个相干脉冲微波,激励氢原子发生Ramsey干涉,从而压缩原子跃迁谱线宽度,提高被动型氢原子钟稳定度性能.利用单片机控制直接数字频率合成器(DDS)产生扫频信号,可以得到完整的Ramsey条纹.目前已观测到Ramsey条纹并成功将原子跃迁谱线宽度压缩至1.2 Hz,仅为传统被动型氢原子钟线宽的40％.%The digital attenuator controlled by Complex Programmable Logic Device (CPLD) outputs two coherent pulsed microwave signals. They interact with hydrogen atoms and induce Ramsey interference. So the line width of hydrogen maser is reduced and the performance of frequency stability could be improved. Single Chip Micyoco(SCM) controls Direct Digital Synthesizer(DDS) to implement frequency sweep. So the Ramsey fringe is obtained. It' s all based on conventional passive hydrogen maser. So far,The Ramsey fringe was observed and its line width is about 1. 2 Hz, which is only 40% of that of conventional passive hydrogen maser in the same condition.