Theoretical analysis of a tilted fiber grating polarizer by the beam tracing approach

摘要

Using the new beam tracing approach of dividing a fiber grating into a pile of infinitesimally thin films and calculating the multiple beam interference of the Fresnel reflections from the thin-film interfaces, a tilted fiber grating based polarizer is theoretically investigated. On the Gaussian fiber mode model, new analytical formulas for expressing the characteristics of the 45° tilted fiber grating polarizer are obtained as the explicit functions of the fiber grating and fiber mode parameters. The present approach provides a clear understanding and fine perspective of all the properties of the tilted fiber grating polarizer, as well as making their quantitative evaluation much easier, as compared with previous works. Our numerical result is shown to be in good agreement with the numerical solution by the volume current method. The achievable polarization performance with different grating parameters is numerically examined and discussed.