Multimodal reflectivity of CRIGF filters: First experimental observation and modelling

Abstract

Cavity Resonator Integrated Guided-mode Resonance Filter (CRIGF) are a new class of filtering reflectors whose selected wavelength and spectral width are independent of the angle of incidence unlike GMRF. These particular properties allow both compactness and a high angular acceptance. However, ours studies show that CRIGFs offer simultaneously spectral and modal filtering and we evidence high-spatial-order reflected modes.In this paper, we will present characterization of the spectral and spatial profile that demonstrates the existence of these high-order modes. In addition, we will present a model based on the physical understanding of implied phenomena to explain the experimental results. This model combines coupled-mode modelling and moiré fringes analysis. These modes could be harnessed for simultaneous spatial and spectral laser stabilization, to design and fabricate selective reflectors or outcouplers for spatial mode division multiplexing (SMDM) in few-mode fibers (FMFs) or for particles optical trapping.

Recent Advances in Resonant Waveguide Gratings

“…A high‐reflection layer can be added to have high reflectance and large phase variations for a subnanometer wavelength shift . Analytical and numerical models have been proposed for efficiently designing such new filters …”

Design of Spectral Filters Based on Linear Polarized Mode Coupling of Optical Fiber

“…Many types of spectral filters are designed and analyzed such as: diffraction grating filters [1][2][3], Fabry-Perot filters [4][5][6], Mach-Zehnder interferometer filters [7][8][9], all fiber filters [9][10][11] and others. Most of all fiber wavelength selective filters which have been drawn in the published papers consist of similar or dissimilar fibers with different shaping of refractive indices [12][13][14][15][16][17][18][19][20]. These filters depend on single mode fibers supporting LP01 in their coupling operation at a range of interesting wavelengths.…”