Effect of the dielectric filling on the phase behaviour of the circular waveguide with azimuthally magnetized ferrite toroid and dielectric cylinder

The phase characteristics of the circular waveguide, comprising an azimuthally magnetized ferrite toroid and a dielectric cylinder of relative permittivity, larger than that of the ferrite, under normal TE₀₁ mode excitation, are figured. The analysis reveals that they are finite for both directions of magnetization, limited by the cut-off frequencies and by specific envelope lines, depending on certain positive real numbers (L numbers), related to the roots of the characteristic equation of the structure. The expansion of the region, occupied by dielectric and the increase of its relative permittivity entails a moving of the position and a shortening of the length of the curves mentioned (a shrinking of the areas of wave propagation), as well as a change of the sign of the differential phase shift provided.