Persons

A new class of quasireflectionless potentials, associated with low energy scattering, has been considered. The effective parameters of low energy scattering have been determined using the system expansion by the wave vectors in the region of the parameters corresponding to the exit of the localized states into the continuum. The parameters of the heterostructures, formed by the composition step-like distribution, which provide the reflectionless conditions in the low-energy region, have been found.

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The design of new types of macromolecular architecture is one of the main directions of development of modern polymer physics. With regard to electronics, a special place is occupied by electrically conductive π-conjugated molecules. The review considers the distinctive features of the electronic properties of organic semiconductors in compare with their solid-state analogs. Special attention is paid to the role of electron-electron and electron-phonon interactions in the formation of autolocalized excited states: solitons and polarons. The constructive and destructive interference effects in molecular structures containing branching nodes and ring groups are discussed. The size of a branched molecule should be not large to preserve quantum coherence. The autolocalization effects in such molecules are not pronounced and transport is provided by electrons and holes injected from electrodes. Two main approaches to the description of quantum interference in branched molecules are desribed in the review: on the basis of molecular orbitals and within localized atomic orbitals picture. These approaches make it possible to formulate design rules for molecular structure exhibiting quantum interference. The recent results are presented on the design of quantum interference molecular transistor with extremely low switching power. Dendrimers, tree-branching nonconjugated molecules, are briefly considered, which can become effective tools for electromagnetic radiation collection and transformation.

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The study results for the THz detectors with a spatial serial and parallel connected transistor structure based on GaAs heterostructure with an asymmetric T-shaped gate in each transistor have been presented. It has been shown that the photovoltaic/photoconductive detectors demonstrate terahertz responses without using additional antenna elements. The sensitivity of up to 1000 V/W and 50 mA/W for the serial and parallel connection of transistors has been measured. An equivalent noise power below 10 W/Hz has been obtained.

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