Comment on Sakli, H. Cylindrical Waveguide on Ferrite Substrate Controlled by Externally Applied Magnetic Field. Electronics 2021, 10, 474

Abstract

Recently, Sakli investigated the propagation of electromagnetic waves in metallic cylindrical waveguides filled with longitudinally magnetized ferrite, focusing on TEz (transverse electric) and TMz (transverse magnetic) modes relative to the z-axis. This commentary highlights that the proposed system generally cannot support the propagation of the TEz and TMz waves, rendering the main results derived by Sakli invalid.