A. A. Lazarenko

We have used the atomic force microscopy and Hall effect measurements to study the influence of InAlAs transition layer design on the electron mobility in the InAlAs/InGaAs/GaAs channel of a highelectron- mobility transistor (HEMT) with the metamorphic buffer. The optimum buffer layer favors suppression of the misfit dislocation threading into upper layers of the HEMT heterostructure and prevents development of the surface microrelief.

Experimental samples of semiconductor heterostructures with GaP_1−x N _x layers and _{In1−x − y} GaP _y N _x and GaP _y N _x As_{1 − x − y} quantum wells are synthesized by molecular beam epitaxy on GaP (001) substrates. The structural properties of the samples are investigated by X-ray diffraction and the molar fraction x of nitrogen in the GaP_{1 − x} N _x layers is determined. To compare the structural and optical properties of the samples, the photoluminescence of epitaxial GaP_{1 − x} N _x layers and heterostructures with InGaPN and GaPAsN quantum wells with GaPN barriers is studied. The photoluminescence and X-ray diffraction data on the GaP_1−x N _x samples are compared with parameters calculated within the band anticrossing model. Based on the experimental and calculated data, it is concluded that the hybridization parameter is not constant and depends on the molar fraction of nitrogen.

It was widely accepted that embedding of metallic layers into optoelectronic structures is detrimental to lasing due to the absorption in the metal. However, recently macroscopic optical coherence and lasing was observed in microcavities with an intra-cavity single metallic layer. Here we propose the design of the of microcavity-type structure with two or more intra-cavity metallic layers which could serve as contacts for electrical pumping. The design of optical modes based on utilizing peculiarities of Tamm plasmon provides vanishing absorption due to the fixing of the node of the electric field of optical mode to metallic layers. Proposed design can be used for fabrication of vertical cavity lasers with intra-cavity metallic contacts.