An efficient contour integral based eigensolver for 3D dispersive photonic crystal

Numerical simulations play a significant role in studying the properties of dispersive metallic photonic crystals. The dispersive photonic crystals are modeled by the Maxwell equations, and the equations are then discretized by the widely-used Yee's scheme. After applying certain similarity transformations to the discretized system, the original simulation problem becomes a non-Hermitian eigenvalue problem with clustered eigenvalues. An efficient contour integral (CI) based eigensolver is developed to overcome the difficulties of applying existing methods to solve eigenvalues in designated regions. This efficient method combines the contour integral, the fast matrix–vector multiplication, and efficient linear system solver. The numerical results illustrate the efficiency of our algorithm.