Evolution of polarization-dependent properties in circular birefringent fiber Bragg gratings and potential application for magnetic field sensing

In this paper the transmission and polarization properties of fiber Bragg gratings with magnetically induced circular birefringence are discussed. The evolutions with wavelength of transmission spectrum and the polarization-dependent parameters for different circular birefringence, grating lengths and input polarizations are analyzed. We demonstrate that the third Stokes parameter and ellipticity evolutions contain the information about the amount of circular birefringence and could thus be used to sensor magnetic field value. Three polarizers are used to detect the absolute values of polarization parameters and hence sense the polarization evolutions.