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The amplification and generation of optical TE waves arising on a lattice formed by a space charge wave in a planar waveguide based on a donor-doped semiconductor (gallium arsenide) n-GaAs are considered. The region of interaction is limited by contacts with a constant electric field applied between them, which, while operating in the Gunn oscillations suppression mode, gener-ates a small-signal periodic inhomogeneity. Reflection and transmission regimes for same-index TE modes propagating in the waveguide structure are investigated depending on the phase mis-match and the pump level. It is shown that even with a relatively small modulation depth of the di-electric constant (about 10–5), under conditions of high optical pumping (with a gain of about 150 cm–1) and a corresponding detuning from phase matching there is the possibility of not only ampli-fying the direct and backward (reflected) optical modes, but also their generation. The advantage of the considered effects is that they enable flexible control of parameters of the dynamic lattice. The results obtained can be used to create semiconductor laser generators based on the interaction of the optical modes and a space charge wave.

Guiding properties of an optical waveguide based on a layered metamaterial formed by layers of iron-yttrium garnet and aluminum-yttrium garnet, magnetized to saturation are considered. Dispersion equations for the waveguide TE and TM modes in the structure were obtained using the approximation of an effective medium and solving the boundary problem (electromagnetic method), and also by means of a 4×4 matrix method. Dispersion spectra of the propagation constant dependence on the cyclic frequency ω(β) for different types of structures are found, localization coefficients of the orthogonal modes in the guiding layer are also derived and their comparative analysis is carried out. The advantages of the approximate electromagnetic method are shown in comparison with the exact 4x4 matrix method. The results of the work can find an application in developing new integrated optical devices for optical signal processing based on layered metamaterials.