Читать книгу Introduction To Modern Planar Transmission Lines - Anand K. Verma - Страница 156

The relative permittivity matrix for gyroelectric medium, under the applied magnetic field in the z‐direction, is expressed as follows:

(4.22)

In the above expressions, ω_p and ω_c are the plasma frequency and cyclotron frequency. The cyclotron frequency is also called the gyrofrequency. The jκ is a cross‐coupling factor responsible for the gyration property of the relative permittivity of a medium. Other parameters are N: electron density, e: electron charge, m: electron mass, and B₀: DC magnetic field. In the case of the extremely high magnetic field, ω_c → ∞ and ε_r = 1, κ = 0. Also, in the absence of magnetic field, B₀ = 0, κ = 0_, and the gyrotropic medium is reduced to a uniaxial dielectric medium. In some cases, there is no plasma medium in the z‐direction and ε_{r, zz} = 1.