Physica Scripta

Development and characterization of 87 Rb atomic ensemble for absolute quantum gravimeter

Anju, Harish Kumar Rathore, Nawaz Sarif Mallick, Abhishek Bhardwaj, Aishik Acharya

Published Nov 1, 2025• 1 citation

Abstract

Abstract The precision measurement of acceleration due to gravity (g) for potential scientific and industrial applications requires the use of absolute quantum gravimeters (AQGs) as quantum sensors. In this study, the development of magneto-optical trap (MOT) for the Rubidium-87 ( 87 Rb) atoms for integration into an atomic gravimeter has been discussed. The MOT serves as a critical component for the cooling and trapping of neutral atoms, providing a high flux, low temperature atomic ensemble for subsequent measurements in cold atomic physics, such as inertial navigation, exploration, and gravity mapping. Our setup emphasizes compactness without compromising atom number or temperature performance using the single 780 nm extended cavity diode laser. We have presented the optimized optical layout for efficient atom cooling, trapping, and detection. The obtained results show atom loading rate of ∼6.02 × 10 8 atoms within 221 ms that provides fast data acquisition for the entire cycle of AQG. The fluorescence signal from free falling MOT is also obtained, which provides time-of-flight of 211 ms and temperature of 57 μK. The system is robust against environmental perturbation and offers valuable insights into the advancement of atomic ensemble for the realization of high precision quantum sensors for geophysical and navigation applications.

DOI: 10.1088/1402-4896/ae1c78

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