Polarization transformation in irregular circular waveguides with helical corrugation and gyrotropic filling

Wave propagation in circular waveguides with helical corrugation of walls and longitudinal gyrotropic filling is considered. The Krylov-Bogoliubov-Mitropolsky method is applied to solution of the perturbed boundary-value problem for electric and magnetic scalar potentials. A system of coupled differential equations for complex amplitudes of propagating waves is obtained in a first approximation of the asymptotic method. A variation of the polarization parameters along the longitudinal coordinate is analyzed. The influence of a combination of helical corrugation and longitudinal gyrotropy for mode and polarization transformation is investigated.