On relaxation of entangled states in a collective thermostat

A kinetic equation describing collective relaxation process in the dispersion limit is derived for an ensemble of two-level atoms placed in a cavity and interacting with one cavity mode. Multiatom entangled states belonging to the set of Dicke states and insensitive to collective decay are found. A scheme for recording, storing, and reading these states with participation of spatially multimode light is reported.     

On Schnabl solutions of string field equations

We clarify the relationship between Schnabl’s solution and pure gauge configurations. Both Schnabl’s and pure gauge solutions are obtained by means of an iterative procedure. We show that the pure gauge string field configuration that is used in the construction of a perturbation series for Schnabl’s solution diverges on a large subspace of string configurations, but it can be rendered convergent by adding a compensating term. The additional term ensures the fulfillment of the equations of motion in a weak sense. This compensating term coincides with the term necessary for obtaining an action consistent with Sen’s first conjecture.     

Integral formulae in the coupled problem of the thermoelasticity of an inhomogeneous body. Application in the mechanics of composite materials

A coupled unsteady problem of thermoelasticity for an inhomogeneous body, described by a system of four second-order partial differential equations with coefficients that vary depending on the coordinates, is considered, and the same problem for a homogeneous body of the same shape (the concomitant problem) is examined together with this original problem. Integral formulae are obtained that allow one to express the displacements and temperature in the original problem in terms of the displacements and temperature in the concomitant problem. Integral formulae are used to represent the solution of the original problem in the form of series over all possible derivatives of the solution of the concomitant problem. A system of recurrence problems is written for the coefficients of these series. Expressions are found for the coefficients of the concomitant problem (effective coefficients) and special boundary value problems are formulated, from the solution of which specific expressions are found for the effective thermoelasticity coefficients. A theorem concerning the fact that the effective coefficients satisfy the physicomechanical constraints imposed on the thermoelastic constants of real bodies is proved. The case of a layer that is inhomogeneous in its thickness is considered and explicit analytical expressions for all the thermoelasticity coefficients are obtained for it. The case when the thermoelasticity coefficients depend periodically on the coordinates is examined in detail.     

Multivelocity models in the theory of heterogeneous media

A study is made of the possibilities of choosing different sets of slow variables in two-component systems with very different masses of the particles in them.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 3, pp. 54–60, May–June, 1991.I am very grateful to E. G. Kolesnichenko for suggesting the problem and his interest in the work.     

A model for calculation of reverse osmosis apparatus of the roll type

A model of reverse osmosis apparatus of the roll type is suggested. The model makes it possible to calculate the working area of the membrane, perform sectioning of the apparatus, determine the working pressure in separating units, and find the energy expenditure for the separation process.Translated from Zhurnal Prikladnoi Khimii, Vol. 77, No. 11, 2004, pp. 1844–1846.Original Russian Text Copyright © 2004 by Abonosimov, Lazarev, Gorbachev.     

Quantum channel for states of light as based on integrals of motion

A method based on integrals of motion for collective processes has been proposed for constructing physical schemes in which the state of one of the subsystems is insensitive to interaction. Decoherence-free quantum channels that allow transmission of an arbitrary light state including the Fock state through an absorbing medium are considered as an example.     

Micromaser operation in correlated atoms

Stimulated emission of two-level atoms in a high-Q cavity is considered under conditions when pumping produces correlated many-atomic states. Based on the many-body problem, a kinetic equation is obtained for the Glauber–Sudarshan probability, which describes the field in the Fokker–Planck approximation. The statistics of light in this approximation are determined by the atomic correlation functions of the order of no higher than the second. The noise of light is found in the regime of micromaser operation for two types of pumping producing the initial separable states with a classical correlation and entangled states. It is shown that the presence of the initial diatomic correlation enhances the intensity noise. The entangled state of atoms is found from which nonclassical light is generated with a steady-state phase and noise, which can be almost completely suppressed in the low-frequency spectral region.     

Kinetics of isothekmal homogeneous nucleation in a quasi-chemical model

Translated from Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki, No. 1, pp. 146–151, January–February, 1991.     

Dependence of viscosity of organic nonassociated liquids on structural and conformational characteristics of the molecules

Semiempirical equations are obtained for the dependence of the viscosity of organic nonassociated liquids on the structural and conformational characteristics of the molecules. The equations are used to compute the viscosities of organic compounds of different structural classes. It is shown that they can be used to take into account the effect of isomerization of the carbon skeleton of the molecule on the viscosity and also the temperature dependence of the viscosity.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 5, pp. 563–567, September–October, 1989.     

Low-temperature implantation of activator atoms into zinc sulfide under stimulation by atomic hydrogen

Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 52, No. 2, pp. 187–191, February, 1990.