The Implementation of a Compact Cold Atom Interference Gyroscope Based on Miniaturized Quartz Vacuum Chamber

The cold atom interference gyroscope (CAIG) offer substantial potential for rotation measurement due to the high sensitivity and stability. The CAIG with a fountain configuration realized by four-pulse could provide a larger interference-loop area, and enhanced performance. However, this kind of CAIG is usually much larger and higher since it requires a vacuum chamber with sufficient height to achieve a long Raman pulse interval. We demonstrate a four-pulse CAIG based on a miniaturized vacuum chamber that enables portable and transportable rotation rate measurements. The main vacuum chamber is realized by whole glass material. The height of the vacuum unit is 0.7 m, the volume is <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${{8}.{86} \times {10}^{{4}}}~{{\textrm {cm}}^{{3}}}$ </tex-math></inline-formula>, and the mass is 75 kg. Then, we estimated the performance of our portable CAIG in the environment of the underground laboratory and the fifth-floor office building. In the laboratory, the sensitivities of the homemade CAIG is <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${4}.{44}\times {10}^{-{6}}$ </tex-math></inline-formula> rad/s<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$/(\text {Hz})^{1/2}$ </tex-math></inline-formula> with an interrogation time of 55 ms and an interference area of 25 mm2. In addition, we measured the angular velocity of the Earth, the relative error is 2.4%. Furthermore, we transported the CAIG to the fifth floor of the office building, which is near the subway. Ultimately, the CAIG achieved a sensitivity of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${5}.{47}\times {10}^{-{4}}$ </tex-math></inline-formula> rad/s<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$/(\text {Hz})^{1/2}$ </tex-math></inline-formula>. Additionally, the theoretical maximum interrogation time achieved by this CAIG is 124 ms corresponding to a sensitivity of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${{5}.{62}\times {10}^{-{8}}}~{/(\text {Hz})^{1/2}}$ </tex-math></inline-formula>. Our new design of the compact CAIG could provide novel insights into the miniaturization of CAIGs, while also pointing out areas for further improvement.