Weakly modulated silicon-dioxide-cladding gratings for silicon waveguide Fabry-Perot cavities

作者：Grote Richard R^*; Driscoll Jeffrey B; Biris Claudiu G; Panoiu Nicolae C; Osgood Richard M Jr

来源：Optics Express, 2011, 19(27): 26406-26415.

DOI：10.1364/OE.19.026406

We show by theory and experiment that silicon-dioxide-cladding gratings for Fabry-Perot cavities on silicon-on-insulator channel ("wire") waveguides provide a low-refractive-index perturbation, which is required for several important integrated photonics components. The underlying refractive index perturbation of these gratings is significantly weaker than that of analogous silicon gratings, leading to finer control of the coupling coefficient kappa. Our Fabry-Perot cavities are designed using the transfer-matrix method (TMM) in conjunction with the finite element method (FEM) for calculating the effective index of each waveguide section. Device parameters such as coupling coefficient, kappa, Bragg mirror stop band, Bragg mirror reflectivity, and quality factor Q are examined via TMM modeling. Devices are fabricated with representative values of distributed Bragg reflector lengths, cavity lengths, and propagation losses. The measured transmission spectra show excellent agreement with the FEM/TMM calculations.

• 出版日期2011-12-19