Multi-wavelength Polarizer Based on Metal Grating-assisted Microstructured Fiber

Multi-wavelength polarizers have many essential applications in optics, quantum communication, Q switch and relating research fields. However, polarizing waveband of the traditional polarizer is restricted in the structure of fibers, which results in finite polarizing wavelengths. In this work, a novel D-shaped microstructure fiber polarizer (DMFP) with metal grating was proposed. Utilizing the abundant harmonic vector characteristics on the surface of metal grating, the DMFP can realize the function of multi-band polarization filtering. Numerical results show that it can achieve three bands of polarization filtering in x-polarized mode from 350 nm to 1600 nm and the resonance wavelengths are periodically modulated by grating. In the meanwhile, by optimizing grating parameters, the number of bands of polarization filtering can be further increased, thus, it fulfills the effective adjustment of polarization filtering. It is promising that metal grating based DMFP has great potential values in the fields of optical filter, communication, and functional devices, etc.