Reconfigurable Optical Magnetometer for Static and Dynamic Fields

Abstract

Optical magnetometers with high resolution, integrability, and reconfigurability have been central to the development of advance photonic devices for remote and efficient magnetic field sensing. These magnetometers have mostly been based on ferromagnetic materials that detect only static magnetic fields. Here, the limitation is overcome by utilizing an interferometric technique to demonstrate a reconfigurable fiber-based magnetometer that is highly sensitive to both static and dynamic magnetic fields. The proposed sensor shows an unprecedented sensitivity of 37.07�nm/mT for static magnetic field that could enable detection of few nanotesla fields with a high-resolution optical spectrometer. Furthermore, the proposed magnetometer has wide dynamic range extending over a frequency band of 0�1700�Hz with significant signal to noise ratio (16.04�dBm at 615�Hz) that enables precise frequency determination of the signal. The large reconfigurability, dynamic operation frequency, and portability of the demonstrated magnetometer ascertain practical applications in broad range of technologies including cardiovascular health monitoring, underground mineral exploration, and marine surveillance. � 2020 Wiley-VCH GmbH