Portable Single-Beam Atomic Total-Field Magnetometer for Stand-off Magnetic Sensing
Abstract
Optically pumped atomic magnetometers (OPAMs) offer high sensitivity at room temperature and are increasingly considered for portable magnetic sensing in geomagnetic-field environments. Here we report a handheld-scale, single-beam scalar Rb OPAM with a sensor-head volume of approximately 110 mL. The device operates in an all-optical Bell-Bloom configuration and uses digital lock-in, dispersive tracking of the Rb Larmor resonance, implemented with a hybrid electronics stack that combines in-house control hardware with commercial modules. A single frequency-modulated laser beam performs both pumping and probing without RF coils. In an unshielded indoor environment, the magnetometer exhibits a noise floor below 6 pT/ near 80 Hz and a measurement bandwidth of 200 Hz. In an unshielded Earth-field deployment, we detect repeatable transient magnetic signatures from a controlled elevator motion sequence and quantify standoff observability over sensor-elevator distances from 1.25 m to 10 m. These results show that compact scalar OPAMs can provide bandwidth and range-resolved event sensitivity suitable for field-deployable magnetic anomaly detection and infrastructure monitoring in realistic geomagnetic environments.
Cite
@article{arxiv.2601.08716,
title = {Portable Single-Beam Atomic Total-Field Magnetometer for Stand-off Magnetic Sensing},
author = {Heonsik Lee and Hyunbeen Lee and Minseok Choi and Yoontae Hwang and Deok-Young Lee},
journal= {arXiv preprint arXiv:2601.08716},
year = {2026}
}
Comments
10 pages, 8 figures