一种用于微小型铷原子频标的6.83 GHz谐振腔

A 6.83GHz Microwave Cavity for Miniaturized Rubidium Atomic Frequency Standard

摘要:

研制了一种用于微小型铷原子频标的6.83 GHz微波谐振腔。对谐振腔内的电磁场、谐振频率与探针的关系进行了分析，并应用Ansoft HFSS软件进行填充介质的谐振腔进行了仿真分析。在此基础上对介质谐振腔进行设计与加工制造，测量出填充不同厚度的氧化铝陶瓷时谐振腔的谐振频率。结果表明，当矩形谐振腔取12 mm × 15 mm × 18 mm，填充5.66 mm厚的氧化铝陶瓷介质，介质谐振腔频率可达6.83 GHz，模式为TE₁₀₁，谐振腔体积大幅减小至3.24 cm³, 是传统的未填充谐振腔体积的三分之一，同时电磁场分布均匀，适用于铷气室型微小型原子频标。

Abstract: This paper presents a 6.83 GHz microwave cavity for miniaturized rubidium atomic frequency standard. Electromagnetic fields in the microwave cavity are analyzed, and relationships of the resonance frequency and the size of the field excitation probe are studied. The Ansoft HFSS software is used to simulate the electromagnetic distributions in microwave cavity. Based on these analyses, the microwave cavity is manufactured. By using the vector network analyzer, the S₁₁ parameters for the micro- wave cavity filled with different thickness of aluminum oxide ceramics are acquired. Tested results demonstrate that the electromagnetic field mode is TE₁₀₁ when the resonance frequency reaches 6.83 GHz, and cavity size is 12 mm × 15 mm × 18 mm with the thickness of filled aluminum oxide ceramics (96%) of 5.66 mm. The volume of the developed 6.83 GHz microwave cavity is 3.24 cm³, which is about 1/3 of the volume of the conventional unfilled cavity. It fits very well for loading the MEMS- based rubidium filter cell and absorption cell for miniaturized rubidium atomic frequency standards. This paper presents a 6.83 GHz microwave cavity for miniaturized rubidium atomic frequency standard. Electromagnetic fields in the microwave cavity are analyzed, and relationships of the resonance frequency and the size of the field excitation probe are studied. The Ansoft HFSS software is used to simulate the electromagnetic distributions in microwave cavity. Based on these analyses, the microwave cavity is manufactured. By using the vector network analyzer, the S₁₁ parameters for the micro- wave cavity filled with different thickness of aluminum oxide ceramics are acquired. Tested results demonstrate that the electromagnetic field mode is TE₁₀₁ when the resonance frequency reaches 6.83 GHz, and cavity size is 12 mm × 15 mm × 18 mm with the thickness of filled aluminum oxide ceramics (96%) of 5.66 mm. The volume of the developed 6.83 GHz microwave cavity is 3.24 cm³, which is about 1/3 of the volume of the conventional unfilled cavity. It fits very well for loading the MEMS- based rubidium filter cell and absorption cell for miniaturized rubidium atomic frequency standards.