| Summary: | Objective is to theoretically and numerically analyze the full spectrum and properties of Transverse Magnetic eigenwaves in a parallel-plate waveguide containing a perfect/imperfect (de)magnetised semiconductor layer sandwiched between two dielectric slabs. The novel contributions in the thesis are summarised as follows. In a perfect demagnetised structure, dynamic modes exist in the frequency band w>cop . (plasma frequency) and two surface plasmonic modes exist in co<COp. The properties of surface plasmons may be qualitatively altered by varying the parameters of dielectric layers. In the lossy demagnetised structure, Effect of loss on the properties and characteristics of eigenmodes and their transformation demonstrates that it strongly depends on parameters of layers which may collectively cause the qualitative changes in the eigenmode spectrum. Poynting vector of plasmonic eigenmodes form vortices at the interfaces as nonzero transverse power flow is towards the central layer where longitudinal power flow is opposite to the surrounding dielectric layers. It provides the consistent interpretation of the eigenmode properties. In particular, the slower plasmonic eigenmodes with higher attenuation has larger transverse power flow than the faster mode with lower attenuation. In a perfect magnetised structure (Voigt configuration), no dispersion curve of propagation mode can cross the line COn=COnTp= J(J)~n + 1 (where OJn=oiale, copn=cojCUe and CUe is the electron cyclotron frequency) and an infinite countable set of dynamic eigenmodes exists at the' frequencies OJn~CUnTp-O while a single nonreciprocal magnetoplasmonic mode propagating in each direction may exist at ml~OJnTp+O. The variation of parameters of dielectric layers qualitatively alters the properties of eigenmode. In the lossy magnetized case, the dispersion and attenuation curves of eigenmodes are continuous. The results show as follows: (1) the transformations of eigenmodes are unexpected and strongly depends on the parameters of layers in the magnetized structure; in asymmetric structures: (2) propagation and attenuation characteristics propagation of eigenmodes is strongly nonreciprocal and in certain frequency bands unidirectional magnetoplasmonic modes can exist; (3) migration of the magnetoplasmonic resonances may increase the bandwidth of the unidirectional propagation of the fast magnetoplasmonic modes without compromising their attenuation rate; (4) thicknesses of the dielectric layers strongly affects the field and power flux distributions in the propagating modes and alter the content of the eigenmode spectrum; (5) the competing effects of nonreciprocal field displacement due to gyrotropy of the magnetised semiconductor layer, reciprocal field displacement due to different permittivities and thicknesses of dielectrics, and losses in the semiconductor layer determine the properties of eigenwaves.
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