Technique for Magnetic Susceptibility Determination in the High Doped Semiconductors by Electron Spin Resonance

Method for determining the magnetic susceptibility in the high doped semiconductors is considered. A procedure that is based on double integration of the positive part of the derivative of the absorption line having a Dyson shape and takes into account the depth of the skin layer is described. Analysis is made for the example of arsenic doped germanium samples at a rather high concentration corresponding to the insulator metal phase transition.Comment: Pages 13, figures 9, references 1

Optical anisotropy of InAs/GaSb broken-gap quantum wells

We investigate in detail the optical anisotropy of absorption of linearly polarized light in InAs/GaSb quantum wells grown on GaSb along the [001] direction, which can be used as an active region of different laser structures. The energy level positions, the wave functions, the optical matrix elements, and the absorption coefficients are calculated using the eight-band k center dot p model and the Burt-Foreman envelope function theory. In these calculations, the Schrodinger and Poisson equations are solved self-consistently taking the lattice-mismatched strain into account. We find that a realistic Hamiltonian, which has the C (2v) symmetry, results in considerable anisotropy of optical matrix elements for different directions of light polarization and different directions of the initial-state in-plane wave vector, including low-symmetry directions. We trace how the optical matrix elements and absorption are modified when spin-orbit interaction and important symmetry breaking mechanisms are taken into account (structural inversion asymmetry, bulk inversion asymmetry, and interface Hamiltonian). These mechanisms result in an almost 100% anisotropy of the absorption coefficients as the light polarization vector rotates in the plane of the structure and in a plane normal to the interfaces

РАЗВИТИЕ МЕТОДОВ ГОСУДАРСТВЕННОГО УПРАВЛЕНИЯ ИНВЕСТИЦИОННЫМИ ПРОЦЕССАМИ С ИСПОЛЬЗОВАНИЕМ ИНВЕСТИЦИОННЫХ РЕСУРСОВ

Owing to the accessibility to funds and resources required to support economics on the whole and most important branches in particular, the state is main investor to real sector of Russian economics. Unfortunately, this investment activity is implemented in the form of «point financing», the financial system being not filled in and comprehensive financial support to the production sphere being not provided for.Основным инвестором на российском рынке инвестиций в реальный сектор экономики является государство, обладающее необходимыми средствами для поддержания экономики и важнейших отраслей. К сожалению, эта инвестиционная деятельность имеет характер точечного финансирования, при этом финансовая система не наполнятся и полноценное финансирование производственной сферы не обеспечивается

Electrical excitation of shock and soliton-like waves in two-dimensional electron channels

We study electrical excitation of nonlinear plasma waves in heterostructures with two-dimensional electron channels and with split gates, and the propagation of these waves using hydrodynamic equations for electron transport coupled with two-dimensional Poisson equation for self-consistent electric potential. The term related to electron collisions with impurities and phonons as well as the term associated with viscosity are included into the hydrodynamic equations. We demonstrate the formation of shock and soliton-like waves as a result of the evolution of strongly nonuniform initial electron density distribution. It is shown that the shock wave front and the shape of soliton-like pulses pronouncedly depend on the coefficient of viscosity, the thickness of the gate layer and the nonuniformity of the donor distribution along the channel. The electron collisions result in damping of the shock and soliton-like waves, while they do not markedly affect the thickness of the shock wave front.Comment: 9 pages, 11 figure

Electrochemical and Photovoltaic Properties of Electropolymerized Poly(thienyl-silole)s

Electrochemical and photoelectrochemical properties were studied of a series of donor−acceptor materials based on polythiophene modified with silole moieties. The materials were prepared by electrochemical anodic polymerization of 2,5-bis([2,2′-bithiophen]-5-yl)-1,1-dimethyl-3,4-diphenylsilole and 2,5-bis([2,2′-terthiophen]-5-yl)-1,1-dimethyl-3,4-diphenylsilole, as well as copolymerization of these monomers with 2,2′-bithiophene. Photocurrent measurements showed that introduction of silole resulted in a considerable enhancement of the photovoltaic properties of silole-containing materials and especially the fill factor. However, as demonstrated by Mott−Schottky measurements, electropolymerized silole-containing materials showed a substantial degree of disorder and high density of states in the midgap, which negatively affected their photovoltaic properties. Atomic force microscopy (AFM) and phase imaging revealed the presence of phase segregation and heterogeneity of the silole-containing materials. Interestingly, introduction of siloles suppressed the cathodic (n-type) doping typical for polythiophenes. This work demonstrates that siloles show great promise as electron-acceptor groups for all-organic solar cells; however, further work is required to optimize the properties and performance of poly(thienylsilole)-based materials

Quality of Life of Kuzbass Coal Industry Workers

The study of the quality of life (QoL) in medicine is recognized worldwide, its scientific study is also recognized as a priority.Aim. To study the quality of life of workers in the Kuzbass coal industry, who are exposed to physical factors, as well as to assess the severity and degree of influence of diseases on QoL.Methods. The method of QoL assessment was based on of individual QoL assessment and the rationing of intensive indicators. For the subjective assessment of the severity of symptoms of the occupational disease (OD) and the effect of these symptoms on QoL, we used the questionnaire method, recommended by Dyakovich M.P. and Kazakova P.V. (2013).Results. The study of individual QoL included 400 miners with OD, caused by exposure to physical factors. We found that among the low indices, reflecting determination of quality of life of workers in the coal industry, satisfaction with the past was the highest. Indices of satisfaction with the future were the lowest. The predominance of subjective positive over negative was possibly related to social satisfaction.The study involved a group of 98 patients, who had symptoms of diseases, caused by exposure to physical factors. Subjective assessment of patients with sensorineural hearing loss (SHL) revealed a significant effect of symptoms of the disease on QoL, especially with regard to symptoms that worsened their psycho-emotional state, which might further lead to impairments and disabilities.Conclusion. Evaluation of individual QoL, as well as the severity of the symptoms and their effect on QoL, helps correctly diagnose the patient’s personal response to the disease, and to evaluate the effectiveness of treatment. In the future, doctors can use the received information when developing rehabilitation measures

Measurement of the neutron electric dipole moment by crystal diffraction

An experiment using a prototype setup to search for the neutron electric dipole moment by measuring spin-rotation in a non-centrosymmetric crystal (quartz) was carried out to investigate statistical sensitivity and systematic effects of the method. It has been demonstrated that the concept of the method works. The preliminary result of the experiment is $d_{\rm n}=(2.5\pm 6.5)\cdot 10^{-24}$ e$\cdot$cm. The experiment showed that an accuracy of $\sim 2.5\cdot 10^{-26}$ e$\cdot$cm can be obtained in 100 days data taking, using available quartz crystals and neutron beams.Comment: 13 pages, 4 figure

Measurement of the neutron electric dipole moment via spin rotation in a non-centrosymmetric crystal

We have measured the neutron electric dipole moment using spin rotation in a non-centrosymmetric crystal. Our result is d_n = (2.5 +- 6.5(stat) +- 5.5(syst)) 10^{-24} e cm. The dominating contribution to the systematic uncertainty is statistical in nature and will reduce with improved statistics. The statistical sensitivity can be increased to 2 10^{-26} e cm in 100 days data taking with an improved setup. We state technical requirements for a systematic uncertainty at the same level.Comment: submitted to Phys. Lett.