Design of Metal Mesh THz Filters Exploiting Adjoint Sensitivity Analysis
Keywords:Adjoint sensitivity, derivative-based optimization, frequency selective surfaces, metal mesh filters, simulation, terahertz filter
We introduce a novel approach for tuning the bandwidth of metal mesh THz filters. Our approach utilizes the adjoint sensitivity with respect to userdefined shape control parameters. Derivative-based optimization is exploited to evolve the initial template of the filter to a new design which satisfies the design specifications. We suggest a smoothing step for the sharp metallic edges that can be implemented in the final structure. Examples are presented to illustrate the efficiency of the technique in tuning the filter’s bandwidth.
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