A high sensitivity magnetometer via the combination of ultrahigh-Q fiber cavity and frequency-locking technology.

The optical cavity with high quality factor (Q) has been successfully employed to improve the sensitivity of magnetometer. However, complex system design and tedious data processing hinder the progress of application, since synchronized with other equipments and undergo additional post-processing. To overcome the limitation, we propose a single-loop frequency-locking (SLFL) optomagnetic (OM) signal solution system (SLFL-OMSS). SLFL-OMSS solution obtained a scale factor of 0.17 mV μT⁻¹ and the peak sensitivity is 44.1 fT/Hz^1/2 at 200 kHz. SLFL-OMSS reduces the calculating and complexity of the OM sensor system, which provides an efficient way for achieving a high-sensitivity OM sensing. [ABSTRACT FROM AUTHOR]