Study of Gallium Nitride/Azobenzene Polymer Grating Coupler

Abstract

Abstract: An integrated optical waveguide grating coupler usinggallium nitride and azobenzene polymer composites was designed, and the characteristics of the device were analyzed by simulation. An integrated optical waveguide directional coupler was constructed using two symmetric gallium nitride ridge optical waveguides on a gallium nitride aluminum substrate, and an azobenzene-containing polymethyl methacrylate polymer was coated as a cladding. Using the photosensitive properties of the azobenzene polymer, a Bragg grating was fabricated by periodic illumination in the region between the two ridge waveguides. The coupling between the modes in the grating coupler was analyzed by the coupled mode theory. Using the coupled mode equations, the output characteristics of each port of the grating coupler were simulated，including the output of each mode as a function of the transmission distance and the amplitude variation under different coupling period conditions.The spectral characteristics of the multi-coupling-period grating coupler were further analyzed. A new scheme was provided to realize the operation of complex spectrum signal in integrated optical path.

Key words: waveguide optics, grating coupler, coupled mode theory, gallium nitride, azobenzene polymer

CLC Number:

TN256

References

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