Reaching a few 10^-15 long-term stability of integrating sphere cold atom clock

【摘要】 We present the long-term stability of the integrating sphere cold atom clock（ISCAC） and analyze its systematic limitations. The relative frequency instability of 2.6 × 10^-15 is reached for an averaging time of 2 ×10⁵ s. The second-order Zeeman effect and the cavity pulling effect in ISCAC, which would induce the frequency drift from the clock transition, are analyzed. The analytical and experimental results indicate that the cavity pulling effect is the main contribution to the long-term frequency instability of the ISCAC. Further technical improvements to the microwave cavity are also discussed.更多还原

【Abstract】 We present the long-term stability of the integrating sphere cold atom clock（ISCAC） and analyze its systematic limitations. The relative frequency instability of 2.6 × 10^-15 is reached for an averaging time of 2 ×10⁵ s. The second-order Zeeman effect and the cavity pulling effect in ISCAC, which would induce the frequency drift from the clock transition, are analyzed. The analytical and experimental results indicate that the cavity pulling effect is the main contribution to the long-term frequency instability of the ISCAC. Further technical improvements to the microwave cavity are also discussed.更多还原