Atoms

Spatially Resolved Precision Measurement of Magnetic Field Using Ultracold Cesium Atoms as Sensors

Anjali Bisht, Manoj Das, Poonam Arora

Published Mar 27, 2025• 2 citations

Abstract

Sub-Doppler laser-cooled cesium-133 atoms are utilized as quantum sensors to achieve precise mapping of magnetic fields across a region in ultra-high vacuum (UHV), with a spatial resolution of 1 cm and a sensitivity of approximately 550 pT/√Hz, enabling accurate measurements within the nanotesla [nT] range. The cold cesium-133 atoms used for magnetic field measurements in this paper are a key component of the cesium fountain frequency standard at CSIR-NPL, which contributes to both timekeeping and magnetic sensing. The results show magnetic field fluctuations within 1 nT with a spatial resolution of 1 cm. The uncertainty in these measurements is of the order of 1.24 × 10−16, ensuring reliable and precise spatially resolved magnetic field mapping.

DOI: 10.3390/atoms13040026

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