Dynamics of the Free Surface of a Conducting Liquid in a Near-Critical Electric Field

Near-critical behavior of the free surface of an ideally conducting liquid in an external electric field is considered. Based on an analysis of three-wave processes using the method of integral estimations, sufficient criteria for hard instability of a planar surface are formulated. It is shown that the higher-order nonlinearities do not saturate the instability, for which reason the growth of disturbances has an explosive character.Comment: 19 page

Hydrodynamic Modes in a Trapped Strongly Interacting Fermi Gases of Atoms

The zero-temperature properties of a dilute two-component Fermi gas in the BCS-BEC crossover are investigated. On the basis of a generalization of the variational Schwinger method, we construct approximate semi-analytical formulae for collective frequencies of the radial and the axial breathing modes of the Fermi gas under harmonic confinement in the framework of the hydrodynamic theory. It is shown that the method gives nearly exact solutions.Comment: 11 page

Mapping of strongly correlated steady-state nonequilibrium to an effective equilibrium

By mapping steady-state nonequilibrium to an effective equilibrium, we formulate nonequilibrium problems within an equilibrium picture where we can apply existing equilibrium many-body techniques to steady-state electron transport problems. We study the analytic properties of many-body scattering states, reduce the boundary condition operator in a simple form and prove that this mapping is equivalent to the correct linear-response theory. In an example of infinite-U Anderson impurity model, we approximately solve for the scattering state creation operators, based on which we derive the bias operator Y to construct the nonequilibrium ensemble in the form of the Boltzmann factor exp(-beta(H-Y)). The resulting Hamiltonian is solved by the non-crossing approximation. We obtain the Kondo anomaly conductance at zero bias, inelastic transport via the charge excitation on the quantum dot and significant inelastic current background over a wide range of bias. Finally, we propose a self-consistent algorithm of mapping general steady-state nonequilibrium.Comment: 15 pages, 9 figure

Research of the possibility of self-excited vibrations amplitude reducing when turning by the variation of the cutting speed

In this paper the results of research of the possibilities of self-excited vibrations suppression in turning by the cutting speed modulation are presented. The experimental approach to conduct the variative control of lathe main drive is described. The possibilities of main drive working in continuous rotation speed mode are researched.В статье приведены результаты исследования возможности подавления автоколебаний при точении модулированием скоростью резания. Описан экспериментальный подход осуществления вариативного управления приводом главного движения токарного станка. Исследованы возможности привода главного движения работы в режиме постоянного варьирования скоростью вращения

On Formation of Anthrasemiquinone in the Conditions of Wood Alkaline Pulping

Electron spin resonance (ESR) and electronic absorbance spectral experiments demonstrate that reversible temperature variation of anion-radica1 concentration in the system anthraqui; none (AQ) - anthrasemiquinone (AS) - anthrahydroquinone (AHQ) in aqueous alka1i is a property of that system and not of the more complicated catalyst-wood system. Lignin model compounds present in low concentrations have no influence on this variation. A raise of radical concentration is accompanied by a change of the solution colour from red into yellow. In pulping conditions AQ can be reduced either by the hydrocarbon or by the lignin component of wood, probably also by numerous organic compounds and even by the alka1i itself. As a result of this process, an AQ-AS-AHQ system is being formed

Quantum simulation of manybody effects in steady-state nonequilibrium: electron-phonon coupled quantum dots

We develop a mapping of quantum steady-state nonequilibrium to an effective equilibrium and solve the problem using a quantum simulation technique. A systematic implementation of the nonequilibrium boundary condition in steady-state is made in the electronic transport on quantum dot structures. This formulation of quantum manybody problem in nonequilibrium enables the use of existing numerical quantum manybody techniques. The algorithm coherently demonstrates various transport behaviors from phonon-dephasing to I-V staircase and phonon-assisted tunneling.Comment: 5 pages, 4 figure

Anomalous Hall effect for the phonon heat conductivity in paramagnetic dielectric

The theory of anomalous Hall effect for the heat transfer in a paramagnetic dielectric, discovered experimentally in [1], is developed. The appearance of the phonon heat flux normal to both the temperature gradient and the magnetic field is connected with the interaction of magnetic ions with the crystal field oscillations. In crystals with an arbitrary phonon spectrum this interaction creates the elliptical polarization of phonons. The kinetics related to phonon scattering induced by the spin-phonon interaction determines an origin of the off-diagonal phonon density matrix. The combination of the both factors is decisive for the phenomenon under consideration.Comment: 5 pages; typos and abstract correcte

Flow structure beneath periodic waves with constant vorticity under strong horizontal electric Fields

While several articles have been written on Electrohydrodynamics (EHD) flows or flows with constant vorticity separately, little is known about the extent to which the combined effects of EHD and constant vorticity affect the flow. This study aims to fill this gap by investigating how a horizontal electric field and constant vorticity jointly influence the free surface and the emergence of stagnation points. Using the Euler equations framework, we employ conformal mapping and pseudo-spectral numerical methods. Our findings reveal that increasing the electric field intensity eliminates stagnation points and smoothen the wave profile. This implies that a horizontal electric field acts as a mechanism for the elimination of stagnation points within the fluid body

Exponential Decay of Correlations in a Model for Strongly Disordered 2D Nematic Elastomers

Lattice Monte-Carlo simulations were performed to study the equilibrium ordering in a two-dimensional nematic system with quenched random disorder. When the disordering field, which competes against the aligning effect of the Frank elasticity, is sufficiently strong, the long-range correlation of the director orientation is found to decay as a simple exponential, Exp[-r/x]. The correlation length {x} itself also decays exponentially with increasing strength of the disordering field. This result represents a new type of behavior, distinct from the Gaussian and power-law decays predicted by some theories.Comment: Latex file (4 pages) + 2 EPS figure