Miniaturized Dual-Beam SERF Magnetometer Using Natural Abundance Rubidium
Jianwei Sheng, Ziao Liu, Xiaoyu Li +3 more
Due to high sensitivity and compactness, spin-exchange relaxation-free (SERF) atomic magnetometers have found widespread applications. These devices rely on alkali atoms to sense magnetic fields, with87Rb being the commonly used isotope. However,87Rb must be extracted from natural abundance rubidium (natRb) through isotopic separation, making it expensive. Replacing87Rb with natRb reduces the cost to approximately just 1%. Nevertheless, it is generally believed that the isotopic mixture of87Rb and85Rb in natRb affects the coherence of the atomic ensemble. Using a dual-beam SERF magnetometer, we systematically compared 3 mm inner-size cubic vapor cells filled with natRb and87Rb. By optimizing the buffer gas pressure and optical parameters, we demonstrate that the natRb magnetometer can achieve performance comparable to that of the87Rb magnetometer. Experimental results show that both cells achieved a sensitivity of 4 1T/Hz1/2. These findings demonstrate that natRb can effectively replace87Rb in miniaturized dual-beam SERF magnetometers, enabling low-cost, high-sensitivity magnetic field measurements.
IEEE International Conference on Electronic Measurement & Instruments•Aug 22, 2025•0 citations