On Mode Bifurcation in Chirowaveguides with Perfect Electric Walls

Modal propagation in chirowaveguides with perfect electric walls is studied. Both the circular cylindrical and the two parallel plate chirowaveguides are considered. Mode bifurcation in the circular chirowaveguide is demonstrated by showing that each mode pair with exp (imØ) and exp (-imø) azimuthal variations have the same cutoff frequency but different phase constants at higher frequencies. In the two parallel plate chirowaveguide, a pair of an odd mode and the next even mode start at the same cutoff frequency, in agreement with the results presented by Engheta and Pelet. We show, however, that the lowest order even mode has no odd counterpart and is therefore the dominant mode in a two parallel plate chirowaveguide.