Reconfigurable Optical Magnetometer for Static and Dynamic Fields

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. A reconfigurable optical magnetometer for active detection of static and dynamic magnetic fields utilizing field modulated cavity interferometry technique is demonstrated. It enables detection of strength and direction of static field at maximum sensitivity of 37.07 nm/mT offering reconfigurable sensitivity and detection range. The magnetometer facilitates dynamic magnetic field detection over a wide frequency range of 0–1700 Hz.