Magnetic-sensitive Ramsey fringes are useful for the magnetic field evaluation of atomic fountain clocks. However, broadening mechanisms affect the visibility of the fringes and limit their application for measurement of the magnetic field. The magnetic-induced Rabi broadening, which comes from the magnetic field inhomogeneity in the microwave cavity of fountain clocks and results in the visibility reduction of the fringes, is demonstrated in this paper. Furthermore, an improved method to shorten the Rabi interaction time is proposed to suppress the broadening effect. Experiments are conducted on the rubidium 87 atomic fountain clock to test the broadening mechanism as well as to demonstrate the effectiveness of the improved method to suppress the broadening effect. As a result, we obtain magnetic-sensitive Ramsey fringes and evaluate the average magnetic field. The second-order Zeeman frequency shift also is evaluated with a fractional frequency shift of ${1.295} \times {{10}^{- 13}}$, and a frequency uncertainty of ${3} \times {{10}^{- 16}}$.

中文翻译：

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磁敏拉姆齐条纹的磁致拉比展宽的评估和抑制

磁敏拉姆西条纹可用于原子喷泉钟的磁场评估。但是，加宽机制会影响条纹的可见性，并限制其在磁场测量中的应用。本文证明了磁诱导的拉比展宽，这是由于喷泉钟的微波腔中的磁场不均匀而导致条纹的可见性降低。此外，提出了一种缩短拉比相互作用时间的改进方法，以抑制加宽效应。在87 87原子喷泉上进行了实验，以测试展宽机理，并证明了改进方法抑制展宽效果的有效性。因此，我们获得了对磁敏感的Ramsey条纹，并评估了平均磁场。二阶Zeeman频移也可通过分数频移估算$ {1.295} \ times {{10} ^ {-13}} $和频率不确定性$ {3} \ times {{10} ^ {-16}} $。