Systematic Determination of Eigenfields in Time and in Frequency Domain

This paper presents numerical procedures applied to the accurate and robust calculation of thousands of eigenfrequencies for lossless resonators. The eigenfield determination is accomplished in two steps. Initially, the finite-integration technique or the finite-element method with higher order curvilinear elements is used, and further, the (B-)Lanczos method with its variations is exploited for the solution of the (generalized) eigenvalue problem. The application to the Bunimovich billiard resonator comparatively assesses the numerical results along with the complementary measurements. Finally, the applicability of the approaches is confirmed and the significant reductions of computational costs are pointed out.