正交偏振探测技术型脉冲光抽运原子钟研究进展

Progress of Orthogonal Polarization Detection Technology in Pulsed Optically Pumped Atomic Clock

介绍了本课题组新概念小型化星载原子钟的研究进展。利用已有的脉冲光抽运技术和独立提出的正交偏振探测技术,将原子钟的钟跃迁信号的对比度从一般吸收法的30%提高到将近100%。该方法主要探测的是光的振幅和相位的总变化,因而能有效提高探测灵敏度和信噪比,从而提高频率稳定度。实验结果表明,正交偏振探测技术原子钟的原子频率稳定度比相同条件下吸收法原子钟的原子频率稳定度提高一个量级;而且在实验的基础上,物理系统的温度稳定度、磁场电流稳定度和激光光强稳定度都能够提高一个量级,正交偏振探测技术原子钟的秒稳能达到1×10-13,天稳能优于1×10-15,将来可能进一步发展并取代氢钟。

The progress of new concept small-size satellite atomic clock in Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, is introduced Base on the pulsed optically pumping （POP） and the orthogonal polarization detection technology, the contrast of the transition signal of atomic clock is improved from 30% in absorption detection to about 100%. The detected result reflects the variation of amplitude and phase of incident light. Therefore, the detection sensitivity and the signal-to-noise ratio are improved effectively, which leads to the improvement of the frequency stability of the atomic clock. Under the same experimental condition, POP atomic clock with orthogonal polarization detection technology has a frequency stability about an order of magnitude higher than the result of POP atomic clock using absorption detection. Above all, when the stabilities of the temperature of physics system, the current of magnetic field, and the intensity of laser are improved by about an order of magnitude, the stability of this atomic clock could reach 1 × 10^-13 for ls and 1× 10 ^-15 for a day, which means that this type of POP atomic clock miuht become a good substitute of the H-maser