Solution of the finite element vector Helmholtz equation by means of eigenvalue displacement

In this paper, after an examination of the spectrum of the system matrix of the discrete vector Helmholtz equation, a novel technique that makes edge finite element matrices more suitable for Lanczos-based solvers is introduced. This technique works by displacing the eigenvalues related to static modes to a more favorable part of the spectrum. The displacement is achieved by means of a matrix that is added to the system matrix.