Design of Grating-Assisted Waveguide Couplers with Weighted Coupling
نویسنده
چکیده
The design of grating-assisted, channel waveguide, codirectional couplers is demonstrated using the Gel’fand-Levitan-Marchenko inverse scattering method. Weighted coupling coefficients are computed from rational function expressions for the desired wavelength response. Approximate formulas are derived which relate the waveguide and grating geometries to the computed coupling coefficients. The technique is illustrated by designing a directional coupler haviag a third-order Butterworth filter characteristic and a 130 A full-width-half-maximum bandwidth.
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