49 research outputs found
Ab-initio simulation of hydrogenated graphene properties
Ab-initio simulation of hydrogenated graphene properties was performed. At present, graphene is considered one of the most promising materials for the formation of new semiconductor devices with good characteristics. Graphene has been the subject of many recent investigations due to its peculiar transport, mechanical and others properties [1]. The chemical modification of graphene named as graphane has recently entered the investigation as a possible candidate to solve problems connected with the lack of a graphene bandgap. Graphane is a compound material consisting of two-dimensional graphene bonded by some atoms of hydrogen. The investigation shows that graphane has the three valley Г-М-K band structure with the Г valley, which has the smallest energy gap between the conductivity zone and the valence zone. The calculation of relative electron masses and non-parabolic coefficients in Г, М and K valleys was performed. Based on the obtained characteristics, it is possible to implement a statistical multi-particle Monte Carlo method to determine the characteristics of electron transfer in heterostructure semiconductor devices. A research on modified graphene structures is important for fundamental science and technological applications in high-speed transistor structures operating in the microwave and very high frequency ranges.Ab-initio simulation of hydrogenated graphene properties was performed. At present, graphene is considered one of the most promising materials for the formation of new semiconductor devices with good characteristics. Graphene has been the subject of many recent investigations due to its peculiar transport, mechanical and others properties [1]. The chemical modification of graphene named as graphane has recently entered the investigation as a possible candidate to solve problems connected with the lack of a graphene bandgap. Graphane is a compound material consisting of two-dimensional graphene bonded by some atoms of hydrogen. The investigation shows that graphane has the three valley Г-М-K band structure with the Г valley, which has the smallest energy gap between the conductivity zone and the valence zone. The calculation of relative electron masses and non-parabolic coefficients in Г, М and K valleys was performed. Based on the obtained characteristics, it is possible to implement a statistical multi-particle Monte Carlo method to determine the characteristics of electron transfer in heterostructure semiconductor devices. A research on modified graphene structures is important for fundamental science and technological applications in high-speed transistor structures operating in the microwave and very high frequency ranges
The research and development of frequency-controlled electric drive
Рассмотрен подход к реализации автономного генератора на базе асинхронного двигателя с фазным ротором с подключением цепи статора к нагрузке и питанием роторных обмоток от регулируемого источника переменного тока, а также определены границы устойчивой генерации электроэнергии.The approach to implement a stand-alone generator based on an induction motor with a wound rotor connected to the stator circuit to the load and the power rotor windings from a regulated source of alternating current, and also defined the boundaries of sustainable electricity generation
Soliton-Magnon Scattering in Two-Dimensional Isotropic Ferromagnets
It is studied the scattering of magnons by the 2d topological
Belavin-Polyakov soliton in isotropic ferromagnet. Analytical solutions of the
scattering problem are constructed: (i) exactly for any magnon wave vectors for
the partial wave with the azimuthal number m=1 (translational mode), and (ii)
in the long- and short-wave limits for the rest modes. The magnon mode
frequencies are found for the finite size magnets. An effective equation of the
soliton motion is constructed. The magnon density of states, connected with the
soliton-magnon interaction, is found in a long-wave approximation.Comment: 4 pages, REVTe