29 April 2016 Determination of the magnetic field induced circular birefringence using the Mueller matrix of FBGs
Author Affiliations +
Abstract
Different methods have already been developed to measure the magnetic field with fiber Bragg gratings (FBGs). They are based on the use of a magnetic fluid or magnetostrictive materials. In addition to these methods, a direct measurement of the magnetic field is also possible by determining the circular birefringence created by the magnetic field inside the fiber. In standard optical fiber, this circular birefringence is of the same order as the intrinsic fiber birefringence or even below. The polarization properties of FBGs are therefore used to perform such measurement since they allow to determine weak birefringence with higher accuracy than standard read-out techniques. However, the obtained accuracy is usually low due to the influence of the intrinsic fiber birefringence. To mitigate this issue, we study in this work the use of the diattenuation vector. This parameter is obtained from the Mueller matrix and we show that it evolves in response to a magnetic field. In practice, we analyze its response by both simulation and experiment. In our simulations, we solve numerically the coupled mode equations of the FBG. For the experiments, the Mueller matrix is measured by an optical vector analyzer for the gratings connected in transmission. We apply an increasing magnetic field on different Bragg gratings photo-written in SMF28 fibers. The rotation of the diattenuation vector is then used to retrieve the magnetic field induced circular birefringence. A linear increase of the reconstructed circular birefringence is reported for increasing magnetic field values in the range 0-1T.
© (2016) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Frédéric Descamps, Sébastien Bette, Damien Kinet, Christophe Caucheteur, "Determination of the magnetic field induced circular birefringence using the Mueller matrix of FBGs", Proc. SPIE 9899, Optical Sensing and Detection IV, 989912 (29 April 2016); doi: 10.1117/12.2227494; https://doi.org/10.1117/12.2227494
PROCEEDINGS
10 PAGES


SHARE
Back to Top