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G. V. Dedkov

Publications and source records attributed to G. V. Dedkov.

At least 19 recordsLinked to original sources
arXiv2022

Nonequilibrium Casimir-Lifshitz force and anomalous radiation heating of a small particle

This paper presents the results of calculating Casimir-Lifshitz friction force and heating rate of a small metal particle moving above a metal surface (thick plate) in the case of their different local temperatures. The case of normal nonmagnetic metals (Au) is considered. There is a strong interplay of temperatures, particle velocity and separation distance resulting in an anomalous direction of the heat flux between the bodies and a peak temperature dependence of the friction force at sufficiently low temperatures. In particular, a hot moving particle can additionally receive heat from a cold surface. The conditions for experimental measurement of these effects are discussed.

cond-mat.mes-hall↗
arXiv2018

A uniformly moving and rotating polarizable particle in thermal radiation field: frictional force and torque, radiation and heating

We study the fluctuation-electromagnetic interaction and dynamics of a small spinning polarizable particle moving with a relativistic velocity in a vacuum background of arbitrary temperature. Using the standard formalism of the fluctuation electromagnetic theory, a complete set of equations describing the decelerating tangential force, the components of the torque and the intensity of nonthermal and thermal radiation is obtained along with equations describing the dynamics of translational and rotational motion, and the kinetics of heating. An interplay between various parameters is discussed. Numerical estimations for conducting particles were carried out using MATHCAD code. In the case of zero temperature of a particle and background radiation, the intensity of radiation is independent of the linear velocity, the angular velocity orientation and the linear velocity value are independent of time. In the case of a finite background radiation temperature, the angular velocity vector tends to be oriented perpendicularly to the linear velocity vector. The particle temperature relaxes to a quasistationary value depending on the background radiation temperature, the linear and angular velocities, whereas the intensity of radiation depends on the background radiation temperature, the angular and linear velocities. The time of thermal relaxation is much less than the time of angular deceleration, while the latter time is much less than the time of linear deceleration.

cond-mat.mes-hall↗
arXiv2018

Friction and Radiative Heat Exchange in a System of Two Parallel Plates Moving Sideways : Levin-Polevoy-Rytov Theory Revisited

It is shown that the fundamental results obtained in the works by Levine, Polevoi, Rytov (1980) and Polevoi (1990), based on the fluctuation-electromagnetic theory by Levine and Rytov, adequately describe the rate of radiative heat exchange and the frictional force in a system of two parallel thick plates in relative lateral motion. A numerically calculated friction force for good metals and thin gaps turns out to be by a factor 107 higher than earlier obtained by Polevoi and increases with increasing conductivity of the metals.

cond-mat.mes-hall↗
arXiv2017

Electrostatic Friction Force on an AFM probe Moving Near a Sample Surface

Within the framework of nonrelativistic electrodynamics, general formulas have been obtained for the tangential dissipative force of electrostatic friction and the normal force of attraction to the surface of an axially symmetric probe moving parallel to the smooth surface of homogeneous materials or coated with thin films substrates with various combinations of materials. As a numerical example, the interaction of a metal ball moving above a metal surface has been studied. The results of the calculations are compared with the available experimental and theoretical results of other authors.

cond-mat.mes-hall↗
arXiv2016

Radiation and Heating of Rotating Neutral Particle in Close Vicinity to the Surface of Transparent Dielectric

We have calculated the intensity of electromagnetic radiation from particles rotating in close vicinity to a transparent dielectric plate. The radiation is a result of quantum and thermal friction occurring during particle rotation, while the driving factor of radiation is a decrease in the kinetic energy of particle. The characteristic frequency of radiation is determined by the angular velocity and the temperature of the plate and surrounding vacuum background. These results are challenging for experimental verification in future.

quant-ph↗
arXiv2016

Rotating Particle in the Near Field of the Surface at Arbitrary Direction of Angular Velocity Vector

We study the fluctuation-electromagnetic interaction between a small rotating particle with an arbitrary direction of angular velocity vector and evanescent field of the heated surface, and obtain the general expressions for the force of attraction, rate of heating and components of torque. The particle rotation dynamics is analyzed. It is shown that during most time of motion the particle slows down provided that a quasiequilibrium thermal state has been reached, while at any initial direction of the angular velocity vector it tends to orient perpendicular to the surface with spin direction depending on the initial conditions. Moreover, the angular velocity vector executes precessional motion around surface normal.

cond-mat.mes-hall↗
arXiv2016

Radiation and Dynamics of Nanoparticle in Equilibrium Background Radiation upon Translational-Rotational Motion

We have obtained general expressions for the intensity of radiation and tangential force of a small polarizable particle in the process of translational-rotational motion in equilibrium radiation background (thermalized photon gas) of certain temperature at an arbitrary relative orientation of the linear and angular velocity vectors. It is shown that in cold vacuum background the translational velocity of particle is independent of time and the intensity of its spontaneous emission is determined by the angular velocity and imaginary part of the polarizability.

quant-ph↗
arXiv2015

On the Dynamics of a Small Rotating Particle Moving in Blackbody Radiation

Based on the general expressions for the tangential force and heating rate of a small polarizable particle during translational-rotational motion in the field of blackbody radiation (in the reference frame of latter),the tangential force in reference frame comoving with particle is calculated. It is this force determines the particle deceleration in the frame of reference of blackbody radiation.

quant-ph↗
arXiv2015

Thermal radiation, radiation force and dynamics of a polarizable particle

We discuss basic expressions and interrelations between various physical quantities describing the fluctuation-electromagnetic interaction of a small polarizable particle during relativistic motion relative to the blackbody radiation, namely tangential radiation force, rate of heating, intensity of thermal radiation/absorption, the change of the rest mass of a particle, and acceleration. We obtain an explicit formula for the frictional force acting on the particle in its rest frame and discuss its connection with the particle acceleration and the tangential force given in the reference frame of background radiation. The criticism of our previous results in recent paper by A. I. Volokitin (Phys. Rev. A81, 2015, 032505) is refuted.

quant-ph↗
arXiv2015

Dynamic van der Waals Interaction of a Moving Atom with the Walls of a Flat Slit

A general expression was obtained for the dynamic energy of the van der Waals interaction of a neutral atom with a flat slit whose walls are characterized by a frequency-dependent dielectric permittivity. The interaction of cesium atoms with the walls of metallic (Au) and dielectric (SiC) slits id analyzed numerically at speeds of 1 E04 to 10 E07 m/s. As the speed of atoms grows, the dynamic potentials near the walls become substantially smaller in magnitude than static potentials, but, in the intermediate region, the former exceed the latter by a factor of 1.5-2.0 m/s in a specific range of speeds.

cond-mat.mes-hall↗
arXiv2014

A uniformly moving polarizable particle in a thermal radiation field with arbitrary spin direction

We have generalized our recent results (Arm. J. Phys., 2014) relating to the dynamics, heating and radiation of a small rotating polarizable particle moving in a thermal radiation field in the case of arbitrary spin orientation. General expressions for the tangential force, heating rate and intensity of thermal and nonthermal radiation are given. It is shown that the intensity of nonthermal radiation does not depend on the linear velocity and spin direction of the particle.

cond-mat.mes-hall↗
arXiv2013

On Thermal Vacuum Radiation of Nanoparticles and Their Ensembles

Radiant emittance of dimers and ensembles of particles consisting of gold, graphite and silica glass nanoparticles in vacuum is studied numerically based on the fluctuation-electromagnetic theory. The presence of neighboring particles of the same temperature causes an oscillating character of radiant emittance (per one particle) depending on the particle size, interparticle distance and temperature. We conclude that an ensemble of particles could be a much more intense source of thermal radiation than an equivalent solid body with the same outer surface area. Alternatively, when the neighboring particles create a significant screening effect (silica), an ensemble of particles could be a very good heat protector.

cond-mat.mes-hall↗
arXiv2013

Fluctuation-Electromagnetic Interaction of Rotating Neutral Particle with the Surface: Relativistic Theory

Based on the fluctuation-electromagnetic theory, we have calculated the retarded force of attraction, frictional moment and heating rate of a neutral particle rotating near a polarizable surface. The particle and surface are characterized by arbitrary material properties and temperatures. The surface is assumed to be in thermal equilibrium with vacuum environment.

cond-mat.mes-hall↗
arXiv2013

Fluctuation-electromagnetic interaction of a small particle with evanescent modes of the surface: impact of translational motion and rotation

Based on the fluctuation-electromagnetic theory, we have calculated tangential (frictional) and normal forces, radiation heat flux and frictional torque on a small rotating particle moving at a nonrelativistic velocity close to a smooth featureless surface. The particle and surface are characterized by different temperatures corresponding to the local thermodynamic equilibrium in their own reference frames.

quant-ph↗