Work

Intrinsic atomic calibration of oscillating magnetic fields in ULF and VLF bands

Year: 2026

Type: article

Abstract: We present a method for absolute calibration of received radio frequency in the ultra-low frequency and very low frequency range. This is achieved with the use of a radio frequency optically pumped magnetometer. We describe a method using an optically pumped sample where the RF broadening of the Cs magnetic resonance allows the magnitude of the received field to be calibrated against the ground-state gyromagnetic ratio of the Cs atoms. This frequency-based calibration avoids the geometric and electrostatic response functions that affect inductive sensors, such as fluxgates, search coils, and SQUID magnetometers. We demonstrate the calibration of magnetic measurement using oscillating magnetic fields in the 300 Hz-20 kHz range and a sensor noise floor of 15 fT Hz-1/2. This radio frequency sensor may be used as a widely tunable narrowband receiver for communication, ranging, or penetrative conductivity imaging.

Source: Review of Scientific Instruments

DOI: 10.1063/5.0304991

Authors: Zak Johnston, Paul F. Griffin, Erling Riis, Dominic Hunter, Marcin Mrozowski, Stuart J. Ingleby

Institution: University of Strathclyde

Language: English

Topic: Atomic and Subatomic Physics Research

Subfield: Atomic and Molecular Physics, and Optics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: hybrid

Funder: Engineering and Physical Sciences Research Council

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