Efficient spin control in high-quality-factor planar micro-cavities

A semiconductor microcavity embedding donor impurities and excited by a laser field is modelled. By including general decay and dephasing processes, and in particular cavity photon leakage, detailed simulations show that control over the spin dynamics is significally enhanced in high-quality-factor cavities, in which case picosecond laser pulses may produce spin-flip with high-fidelity final states.Comment: 6 pages, 4 figure

Этническо-культурные и национальные особенности украинского народа в идеях Кирилло-Мефодиевского общества

В даній публікації розробляється проблема визрівання корінних причин становлення політичних етнічно-культурних та національних особливостей українців у контексті історичного, культурного, політичних вимірів. Доведено, що кирило-мефодіївці розуміли причини етнічно-культурного розмежування, які мають історико-духовні витоки з минулого часу. Обґрунтовано тезу, що члени Кирило-Мефодіївського товариства намагалися визначити варіативний напрямок в розвитку національно-духовної згуртованості українців. Було зазначено, що характерною рисою українського народу в своїй основі мають домінуючі принципи: поваги до сімейних родинних відносин, любові до рідної землі, яка є колискою становлення суспільства, раціонального-філософського світобачення, гідне відношення до іншого людського життя. Обґрунтовано тезу про те, що вплив на філософію та політичні позиції Кирило-Мефодіївського товариства мали ідеї європейських традиційних. Звернуто увагу на те, що теоретичною та методологічною основою в аналіз становлення політичних, етнічно-культурних та національних особливостей українців лягли праці українських та зарубіжних філософів, політологів, культурологів, та було підкреслено, що ними були розроблені філософські категорії, методи дослідження, стосовно теми розвитку етнічно-культурних та національних особливостей українців та формування політичного мислення української нації.This publication is developed root causes of the problem of maturing political formation of ethnic, cultural and national peculiarities of Ukrainian in the context of historical, cultural and political dimensions. Proved that Cyril and Methodians understand the causes of ethnic and cultural distinction that have historical and spiritual origins of the past. Proved the thesis that members Cyril Mefodiyivskoho Variadic company tried to determine the direction in the development of national and spiritual unity Ukrainian. It was noted that a characteristic feature of the Ukrainian people basically have the dominant principles: respect for the family of family relationships, love the motherland, which is the cradle assembly society, rational and philosophical worldview worthy relationship to another human life. Grounded thesis that the impact on philosophy and political positions Cyril and Methodius had the idea of European traditional. Attention is paid to the fact that the theoretical and methodological basis for the analysis of formation of political ethno-cultural and national peculiarities of Ukrainian went to work Ukrainian and foreign philosophers, political scientists, culture, and emphasized that they were developed philosophical categories, research methods, in relation to the theme of ethnic cultured and national peculiarities of Ukrainian political thought and the formation of the Ukrainian nation.В данной публикации разрабатывается проблема вызревания коренных причин становления политических, этнически-культурных и национальных особенностей украинцев в контексте исторического, культурного, политических измерений. Доказано, что кирилло-мефодиевцы понимали причины этнокультурного разграничения, которые имеют историко-духовные истоки из прошлого времени. Обосновано тезис, что члены Кирилло-Мефодиивского общества пытались определить вариативное направление в развитии национально-духовной сплоченности украинского народа. Было отмечено, что характерной чертой украинского народа, в своей основе, имеют доминирующие принципы: уважения к семейно-родственным отношениям, любви к родной земле, которая является колыбелью становления общества, рационального философского мировоззрения, достойное отношение к другой человеческой жизни. Обоснован тезис о том, что влияние на философию и политические позиции Кирилло-Мефодиевского общества имели идеи европейских традиционных идей. Обращено внимание на то, что теоретической и методологической основой в анализ становления политических, этнически-культурных и национальных особенностей украинцев легли труды украинских и зарубежных философов, политологов, культурологов, и было подчеркнуто, что ими были разработаны философские категории, методы исследования, относительно темы развития этническо-культурных и национальных особенностей украинского народа и формирования политического мышления украинской нации

Investigation of coaxial laser cladding process parameters influence onto single pass clad geometry of tool steel

ArticleThis paper is devoted to the investigation of the influence of technological parameters on the single pass clad geometry and quality as well as elemental composition in the clad after coaxial laser cladding (CLC). The objects of the investigation are components of expensive machines and tools for presswork needed to be repaired, i.e. refurbished for the future application with the goal of effective using of material resources in production. Nowadays such repair of worn tools is an actual task due to tendency for thrifty management of resources at affordable cost. Experimental work was carried out using CLC system, which consists of industrial robot and a ytterbium fiber laser with a core diameter of 100 μm, integrated to the coaxial powder supplying cladding head. During research separate cladding tracks of metal powder AISI М2 (particle size 53–150 μm) were deposited on the top surface of steel plates, which were grinded before treatment. This work’s highlighted parameters for variation were laser scanning speed and laser beam focus plane distance. The clad geometry was examined on cross-sections with SEM. Elemental composition was determined by the X-ray spectroscopy analysis. Gladding beads with good surface quality were achieved. Cross-sectional observation presented that clads has a good fusion with the base material without exfoliation. Keyhole shape of molten substrate area was achieved, which leads to increase of the dilution value. The future research is needed to achieve stable quality of cladding, which is extremely necessary for industry

Spin susceptibility in superconductors without inversion symmetry

In materials without spatial inversion symmetry the spin degeneracy of the conduction electrons can be lifted by an antisymmetric spin-orbit coupling. We discuss the influence of this spin-orbit coupling on the spin susceptibility of such superconductors, with a particular emphasis on the recently discovered heavy Fermion superconductor CePt3Si. We find that, for this compound (with tetragonal crystal symmetry,) irrespective of the pairing symmetry, the stable superconducting phases would give a very weak change of the spin susceptibility for fields along the c-axis and an intermediate reduction for fields in the basal plane. We also comment on the consequences for the paramagnetic limiting in this material.Comment: 10 pages, 3 figure

Optimal design of turbines taking into consideration the mode of operation

The technique of turbines parameters optimization taking into consideration a variable mode of their operation has been developed. Block-hierarchical representation of design process is used. The hierarchy of local optimization problems is organized by a functional sign and realized in a common information space. The structure of optimization technique is shown, and also the analysis of the data streams uniting these problems in unified process of optimal design is resulted. By means of the developed technique optimal design of the 4-stage turbine expander with rated power 4 MW has been performed. Results of the design are presented and analyzed

Transitions/relaxations in polyester adhesive/PET system

The correlations between the transitions and the dielectric relaxation processes of the oriented poly(ethylene terephthalate) (PET) pre-impregnated of the polyester thermoplastic adhesive have been investigated by differential scanning calorimetry (DSC) and dynamic dielectric spectroscopy (DDS). The thermoplastic polyester adhesive and the oriented PET films have been studied as reference samples. This study evidences that the adhesive chain segments is responsible for the physical structure evolution in the PET-oriented film. The transitions and dielectric relaxation modes’ evolutions in the glass transition region appear characteristic of the interphase between adhesive and PET film, which is discussed in terms of molecular mobility. The storage at room temperature of the adhesive tape involves the heterogeneity of the physical structure, characterized by glass transition dissociation. Thus, the correlation between the transitions and the dielectric relaxation processes evidences a segregation of the amorphous phases. Therefore, the physical structure and the properties of the material have been linked to the chemical characteristics

Can Hall drag be observed in Coulomb coupled quantum wells in a magnetic field?

We study the transresistivity \tensor\rho_{21} (or equivalently, the drag rate) of two Coulomb-coupled quantum wells in the presence of a perpendicular magnetic field, using semi-classical transport theory. Elementary arguments seem to preclude any possibility of observation of ``Hall drag'' (i.e., a non-zero off-diagonal component in \tensor\rho_{21}). We show that these arguments are specious, and in fact Hall drag can be observed at sufficiently high temperatures when the {\sl intra}layer transport time $\tau$ has significant energy-dependence around the Fermi energy $\varepsilon_F$. The ratio of the Hall to longitudinal transresistivities goes as $T^2 B s$, where $T$ is the temperature, $B$ is the magnetic field, and $s = [\partial\tau/ \partial\varepsilon] (\varepsilon_F)$.Comment: LaTeX, 13 pages, 2 figures (to be published in Physica Scripta, Proc. of the 17th Nordic Semiconductor Conference