Nonreciprocal Transmission of Electromagnetic Waves Using an Electric–Gyrotropic Dispersive Medium

A nonreciprocal transmission structure is designed using a one-dimension multilayer medium, which consists of two asymmetric structure filled with the electric–gyrotropic dispersive media. The total transmission coefficients have been deduced using the transfer matrix method. Numerical results further provided evidence for the occurrence of the nonreciprocal surface electromagnetic waves. These states are affected by the thickness of layers, incident angles, and the externally applied magnetic fields. Given that the electric–gyrotropic media are inherently dispersive, our investigations will contribute to the practical application of nonreciprocal structures.

Фотонные кристаллы на основе сред с произвольной анизотропией диэлектрической и магнитной проницаемостей

A general approach to analyzing eigenmodes in anisotropic and gyrotropic 3D photonic crystals based on dielectric and magnetic media is proposed. This approach is based on the representation of stationary macroscopic Maxwell equations in the operator form corresponding to the quantum-mechanical equation for a photon with spin s = 1. In these equations, the strengths of electric and magnetic fields are put into correspondence with state vectors in the complex Hilbert space. The permittivity and permeability serve as operators acting on these vectors. It is shown that the problem of determining the eigenmodes of a photonic crystal is reduced to searching for eigenvectors and eigenvalues of the Hermitian operator characterizing the spin–orbit interaction of a photon in the periodic anisotropic medium under study. It is proposed to use photon states with a certain wave vector (certain momentum) and a certain linear or circular spin polarization as a basis for the representation operator equations. One-dimensional photonic crystals are considered as an example. The influence of anisotropy and gyrotropy on the dispersion of eigenmodes in these crystals is investigated. The group velocity of the eigenmodes, momentum transferred by them, and spin angular momentum are analyzed for the case of gyrotropic media.