Recent advances and applications on fiber-optic scalar and vector magnetometers

The increasing use of nanomaterials and scalable, high-yield fabrication processes is revolutionizing the development of fiber-optic magnetic field sensors. Over the past decades, research on magnetically sensitive materials-mediated magnetic field sensing has been at the forefront due to their potential scientific and industrial applications. The advancement in magnetometry science relies on a better understanding of theory, manufacturing, and fabrication practices, and application-specific methods. The topology and properties of the fiber-optic magnetometers can be changed by incorporating different manufacturing processes, which separate them from their bulk counterparts. Several scalar and vector magnetometers have been proposed in the recent past by exploiting the coating of magneto-optical materials like yttrium iron garnet, silk fibroin hydrogel, Fe3O4/NiFe2O4 plasmons, magnetostrictive materials like Trefenol-D, etc., on different fiber-optic configurations, which can precisely measure the different ranges of the magnetic field with high sensitivity. Furthermore, due to their inherent advantages, these engineered-materials-integrated transducing optical devices have broadened the scope of magnetometers' utilization in numerous disciplines, ranging from modest to most specialized and challenging circumstances. This review provides a comprehensive overview of magneto-sensitive coating material-based interfacing technologies, including composite fiber-optic magnetic field sensors, and a summary discussion of these magnetometers' proven applications and emerging uses.