Propagation Characteristics of a Partially Filled Cylindrical Waveguide for Light Beam Modulation

Propagation characteristics of a cylindrical waveguide partially filled with a cylindrical dielectric light modulation material is analyzed and numerical computation is performed for a few typical cases. This type of traveling-wave structure supports a TE or TM mode, and therefore is useful for light beam modulation applications requiring a longitudinal magnetic or electric field. Numerical analysis indicates that for the TM case, a broadband region occurs near a crossover point and broadband synchronization between the modulating microwave and the parallel-launched light beam can be obtained by a suitable choice of the dielectric medium surrounding the central dielectric.