On the spectrum of a Hamiltonian defined on su_q(2) and quantum optical models

Analytical expressions are given for the eigenvalues and eigenvectors of a Hamiltonian with su_q(2) dynamical symmetry. The relevance of such an operator in Quantum Optics is discussed. As an application, the ground state energy in the Dicke model is studied through su_q(2) perturbation theory.Comment: 11 pages, LaTeX, content change

Results of applying acidic hydraulic fracturing with proppant in the Tournaisian-Famennian reserves at the Ozernoe field

The paper is devoted to the efficiency of acidic hydraulic fracturing – the most widespread method of well stimulation for the Tournaisian-Famennian carbonate reserves found in the Ozernoe field. All the operations performed may be divided in two groups: acidic hydraulic fracturing performed by the conventional technology when fracture openness is reached by wall profile following the reaction of acid with rock, and acidic hydraulic fracturing with proppant. At the site investigated 12 operations of proppant fracturing were performed. To assess the results, including comparison with the conventional acidic hydraulic fracturing, the well investigation data were obtained under nonsteady flow before and after the treatment. In doing so, pressure build up curves were processed by standard methods and that of Warren-Root to evaluate fracturing level. Two wells were chosen with similar production profile and formation flow characteristics prior to well intervention, which were explored twice afterwards. The reservoir was classified as porous for both wells in accordance with pressure build up curve. Following acidic hydraulic fracturing in both cases reservoir fracturing was observed with average fracture openness from 10 to 30 µm. However, nine months after the intervention no fracture were found in the well subjected to conventional acidic hydraulic fracturing, with the same formation flow and production characteristics as before the intervention. The well processed by proppant acidic hydraulic fracturing demonstrates fracturing immediately after the intervention and almost two years later, which testifies to the technology efficiency. The conclusions made were confirmed by field data

A Modified Electrochemical Model to Account for Mechanical Effects Due to Lithium Intercalation and External Pressure

For a battery cell, both the porosity of the electrodes/separator and the transport distance of charged species can evolve due to mechanical deformation arising from either lithium intercalation-induced swelling and contraction of the active particles or externally applied mechanical loading. To describe accurately the coupling between mechanical deformation and the cell\u27s electrochemical response, we extend Newman\u27s DualFoil model to allow variable, non-uniform porosities in both electrodes and the separator, which are dynamically updated based on the electrochemical and mechanical states of the battery cell. In addition, the finite deformation theory from continuum mechanics is used to modify the electrochemical transport equations to account for the change of the charged species transport distance. The proposed coupled electrochemomechanical model is tested with a parameterized commercial cell. Our simulation results confirm that mass conservation is satisfied with the new formulation. We further show that mechanical effects have a significant impact on the cell\u27s electrochemical response at high charge/discharge rates

The Minimum-Uncertainty Squeezed States for for Atoms and Photons in a Cavity

We describe a six-parameter family of the minimum-uncertainty squeezed states for the harmonic oscillator in nonrelativistic quantum mechanics. They are derived by the action of corresponding maximal kinematical invariance group on the standard ground state solution. We show that the product of the variances attains the required minimum value 1/4 only at the instances that one variance is a minimum and the other is a maximum, when the squeezing of one of the variances occurs. The generalized coherent states are explicitly constructed and their Wigner function is studied. The overlap coefficients between the squeezed, or generalized harmonic, and the Fock states are explicitly evaluated in terms of hypergeometric functions. The corresponding photons statistics are discussed and some applications to quantum optics, cavity quantum electrodynamics, and superfocusing in channeling scattering are mentioned. Explicit solutions of the Heisenberg equations for radiation field operators with squeezing are found.Comment: 27 pages, no figures, 174 references J. Phys. B: At. Mol. Opt. Phys., Special Issue celebrating the 20th anniversary of quantum state engineering (R. Blatt, A. Lvovsky, and G. Milburn, Guest Editors), May 201

Морфологические, оптические и фотолюминесцентные свойства тонких пленок ZnO на подложке Al2O3

Тонкие прозрачные проводящие пленки оксида цинка представляют интерес для применения в различных областях науки и техники, в том числе в антиобледенительных системах стекол в самолетах, в покрытиях, уменьшающих статический электрический заряд на панелях измерительных приборов, в электрических контактах к жидким кристаллам, электрохромных и электролюминесцентных индикаторах для дисплеев, разработках высокоэффективных солнечных элементов. Thin transparent conductive zinc oxide films are of interest for application in various fields of science and technology, including anti-icing systems for glasses in aircrafts, in coatings that reduce static electric charge on instrument panels, in electrical contacts to liquid crystals, electrochromic and electroluminescent indicators for displays, development of high-efficiency solar cells

A Group-Theoretical Approach to Quantum Optics: Models of Atom-Field Interactions

Written by major contributors to the field who are well known within the community, this is the first comprehensive summary of the many results generated by this approach to quantum optics to date. As such, the book analyses selected topics of quantum optics, focusing on atom-field interactions from a group-theoretical perspective, while discussing the principal quantum optics models using algebraic language. The overall result is a clear demonstration of the advantages of applying algebraic methods to quantum optics problems, illustrated by a number of end-of-chapter problems. An invaluable