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We study the electromagnetic diffraction by gratings and random rough surfaces. The C-method is an exact method developed for this aim. It is based on Maxwell´s equations under covariant form written in a nonorthogonal coordinate system. The C-method leads to an eigenvalue problem, the solution of which gives the diffracted field. We focus on the numerical aspect of the C-method, trying to develop an efficient application of this exact method. For gratings, we have developed a new version of the C-method which leads to a differential system with initial conditions. This new version of the C-method can be used to study multilayer gratings with a homogeneous medium. We implemented high performance algorithms for the original versions of the C-method. Especially, we have developed a specifically designed parallel QR algorithm for the C-method and spectral projection method to solve the eigenvalue problem more efficiently. Experiments have shown that the computation time can be reduced significantly.

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After obtained a PhD in Computer Science from Paris-Saclay University, this author did his postdoctoral research within INRIA and then in UC Berkeley as a visiting scholar.He currently works in a high-tech company as an Algorithm Engineer. His research interests mainly lie in parallel algorithms designing, code optimization and machine learning.

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