2024/06/27 by Alan McWilliam, McWilliam, A. P., S. Dyer +17
Engineering · Physics and Astronomy · #Atomic Physics (physics.atom-ph) #Atomic and Subatomic Physics Research #FOS: Physical sciences #Magnetic Field Sensors Techniques #Magnetic properties of thin films
paper · pdf · doi:10.48550/arxiv.2406.19178
openalex publication_date 2024/06/27 · openalex created_date 2024/06/29 · openalex updated_date 2026/07/28
The microfabrication of cesium vapor cells for optically pumped magnetometry relies on optimization of buffer gas pressure in order to maximize atomic coherence time and sensitivity to external magnetic signals. We demonstrate post-bond nitrogen buffer gas pressure tuning through localized heating of an integrated micro-pill dispenser. We characterize the variation in the intrinsic longitudinal relaxation rate, γ10, and magnetic sensitivity, as a function of the resulting nitrogen buffer gas pressure. Measurements are conducted through employing an optically pumped magnetometer operating in a free-induction-decay configuration. γ10 is extracted across a range of nitrogen pressures between ∼~60~-~700~Torr, measuring a minimum of 140~Hz at 115~Torr. Additionally, we achieve sensitivities as low as 130 ~fT/√(Hz) at a bias field amplitude of ∼ 50~μT. With the optimal nitrogen buffer gas pressure now quantified and achievable post-fabrication, these mass-producible cells can be tailored to suit a variety of sensing applications, ensuring peak magnetometer performance.