【摘要】 中国计量院自2006年开始进行锶原子光晶格钟研究,于2015年对光钟系统不确定度进行初步评估,并做绝对频率测量。为了提升系统的性能,利用30cm长参考腔进一步压窄钟跃迁激光的线宽,并通过能量滤波的方式使得光晶格中原子的温度降低到轴向2.5μK和径向3.8μK。原子跃迁谱线最窄达到1.65Hz。通过分时自比对的方法,得到光晶格钟频率测量稳定度为2E-15/t^1/2,在40000s内,光晶格钟的测量稳定度进入E-18量级。更多还原

【Abstract】 The National Institute of Metrology of China（ NIM） has been researching Strontium optical lattice clock since 2006 and conducted the first preliminary evaluation and absolute frequency measurement in 2015. To further improve its performance,the linewidth of the clock laser is narrowed by referencing to a 30-cm-long ultra-stable cavity,and the energy filter scheme is used to reduce the temperature of atoms in the lattice to 2. 5μk in the longitudinal axis and 3. 8μk in the radial direction. The narrowest linewidth of the clock transition reaches about 1. 65 Hz. With time-interleaved self-comparison method,the measurement stability of the optical lattice clock is 2 E-15/t^1/2 and reaches E-18 within 40,000 s.更多还原