Complex Resonance As a Self-Consistent Electromagnetic Process

The phenomenon, which is classified as a complex resonance and takes place in electromagnetic structures described by nonself-adjoint boundary value problems, is considered. It is shown that the oscillation adjoint to a source is formed, when complex waves that are complex conjugate by wave numbers and amplitudes are excited in couples. This oscillation is described by the self-consistent boundary value problem for the adjoint Helmholtz equation, i.e., for the equation, whose right-hand side is the solution of the homogeneous boundary value problem. The distinctive feature of the complex resonance is in the fact that it exists in the whole range of complex waves, when the source is necessarily present. Theoretical and experimental results of the investigation of the considered phenomenon are presented.