Cylindrical Vector Beam for Magneitc Field and Temperature Sensing Based on Magnetic Nanoparticle Suspensions

We propose an approach to magnetic and temperature sensing based on cylindrical vector beam (CVB) with radial polarization distribution. The measurement principle relies on the inhomogeneous of magnetic nanoparticle suspensions under external magnetic field, which leads to different transmittance between the light polarization parallel and perpendicular to magnetic field after passing through the suspensions. A CMOS camera is utilized to record the beam distribution profile and extract the corresponding polarization intensity. In this way, the cross-sensing matrix can be formed by analyzing the relationship between the two orthogonal polarizations and sensing parameters. The obtained results can contribute to exploring the application of vector beam in sensing.