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G. V. Dedkov

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

At least 37 records · Page 2Linked to original sources
arXiv2013

Tangential force, Frictional Torque and Heating Rate of a Small Neutral Rotating Particle Moving through the Equilibrium Background Radiation

For the first time, based on the fluctuation-electromagnetic theory, we have calculated the drug force, the radiation heat flux and the frictional torque on a small rotating particle moving at a relativistic velocity through the equilibrium background radiation (photon gas). The particle and background radiation are characterized by different temperatures corresponding to the local thermodynamic equilibrium in their own reference frames.

cond-mat.other↗
arXiv2012

Impact of Rotation on the Retarded Interaction between a Permanent Dipole Particle and a Polarizable Surface

We have calculated components of torque and the interaction energy of small rotating particle with a permanent dipole moment in the case where the rotation axis is perpendicular to the surface and the dipole axis is inclined to it. The retardation effects were taken into account. An important property of this system is its quasistationarity. When the dipole axis coincides with the rotation axis, the particle does not experience damping and may revolve for infinitely long time. When the axis of dipole particle is inclined to the surface, the situation is possible where the particle is repelled off the surface and its spin increases.

cond-mat.other↗
arXiv2012

Fluctuation-Electromagnetic Interaction: Effects of Uniform Motion, Rotation, and Thermal Disequilibrium

In this work, we give a consistent review of recent analytical results of reference character related to the fluctuation-electromagnetic interactions in the systems particle-vacuum, particle-surface, particle-particle, and surface-surface. Effects of dynamical, rotational, and thermal disequilibrium are considered. The applications of these results are important in atomic and molecular physics, quantum field theory and nanotechnology.

cond-mat.mes-hall↗
arXiv2012

Fluctuation-Electromagnetic Interaction between Rotating Nanoparticles. 2.Relativistic Theory

We study the fluctuation electromagnetic interaction in a system of two rotating electrically neutral nonmagnetic particles with allowance for relativistic retardation effect. The particles are assumed to have different temperatures being embedded into a heated vacuum background (photon gas). Closed expressions for the free energy, frictional torque and the rate of heat transfer are derived and compared to the known static results and those in the electrostatic limit without retardation.

cond-mat.mes-hall↗
arXiv2012

Impact of Rotation on the Interaction of a Small Dipole Particle with Dielectric Surface

We have calculated components of the torque and the interaction energy of rotating dipole particle in the case where the rotation axis is perpendicular to the surface and the dipole axis is inclined to it. An important property of this system is its quasistationarity. When the dipole axis coincides with the rotation axis, the particle does not experience braking and may revolve for infinitely long time. When the dipole axis is inclined to the surface, a situation is possible where the particle is repelled off the surface provided that the rotation frequency is tuned to the absorption resonance of the surface. The established effects are important in trapping and manipulating rotating nanoparticles close to the surface.

cond-mat.mes-hall↗
arXiv2012

Fluctuation Electromagnetic Interaction Between Rotating Nanoparticle and Near-Field of the Surface

Fluctuation electromagnetic interaction between a small rotating particle and a polarizable surface produces the friction torque on the particle, changes the attraction force (van -der -Waals force) and the rate of heat exchange in this system. In this paper we consider the case where the rotation axis is parallel to the surface. We present general theoretical basis allowing to obtain characteristics of the interaction at an arbitrary orientation of the rotation axis. In comparison to the case where the rotation axis is perpendicular to the surface (arXiv: 1208.2603), the obtained integral expressions for the friction torque, interaction energy and heating rate have different numerical coefficients. Numerical estimations are given in the case Au (particle)- Au(surface) and SiC (particle)-SiC (surface).

cond-mat.other↗
arXiv2012

Fluctuation Electromagnetic Interaction Between Small Rotating Particle and a Surface

We study fluctuation electromagnetic interaction between small neutral rotating particle and polarizable surface. The attraction force, friction torque and heating are produced by the particle polarization and fluctuating near-field of the surface. Closed analytical expressions are found for these quantities assuming that the particle and surface are characterized by the frequency dependent polarizability and dielectric permittivity and different temperatures. It is shown that the stopping time of the rolling particle in the near-field of the surface is much less than the stopping time under uniform motion and rolling in vacuum space.

cond-mat.other↗
arXiv2012

Controversies and Progress in the Problem of Dynamical Fluctuation-Electromagnetic Interactions

A review is given of the key works relevant to the problem of dynamical fluctuation-electromagnetic interaction, a problem of topical interest over a period of several decades. We discuss controversies and present day progress in this problem considering two basic geometrical configurations: a small particle moving above a plate, and two parallel plates in relative motion.

cond-mat.other↗
arXiv2011

On Thermal Radiation of Black Holes

We calculate the photonic frequency-dependent absorption cross section and intensity of the Hawking radiation for a stationary non-rotating black hole using the electrodynamic membrane paradigm and Kirchhoff's law. A remarkable conclusion is that the use of geometrical optics limit for absorption cross-section and Kirchhoff's law for the photonic luminosity of black hole provides a very good estimation for its total emission power

physics.gen-ph↗
arXiv2011

Dynamical Casimir-Polder Force between a Metallic Particle and a Perfectly Conducting Plate

For the first time, we have studied the impact of magnetic polarizability of a neutral metallic particle on the dynamical Casimir-Polder force, when the particle is uniformly moving with relativistic velocity parallel to the surface of an ideally conducting plate. The material properties of particle are taken into account within the Drude model approach.

cond-mat.other↗
arXiv2011

Dynamical Casimir-Polder atom-surface interaction

We have calculated dynamical Casimir-Polder interaction force between a moving ground state atom and a flat polarizable surface. The velocity of an atom can be close to the velocity of light. The material properties are taken into account using a single oscillator model of the atomic dynamic polarizability and the Drude dielectric function of a metal substrate. The limit cases of nonrelativistic velocities and an ideal metal substrate are also considered. We have found specific dependence of the calculated forces on the velocity (energy), distance and material properties.

cond-mat.other↗
arXiv2011

Nonrelativistic theory of electromagnetic forces on particles and nanoprobes moving near a surface

Closed nonrelativistic (nonretarded) theory of conservative and dissipative electromagnetic forces and heat exchange between moving particles (nanoprobes) and a surface (flat and cylindrical) is reviewed. The formalism is based on methods of classical and fluctuating electrodynamics using minimum assumptions. The spatial dispersion effects are introduced via the surface response functions. The theory allows to treat various problems related with dynamic interactions of charged particles, dipole molecules, neutral atoms and nanoprobes in a unified manner. For the first time, a brief review of the recently obtained consistent relativistic results is also given. The corresponding formulae exactly reduce to the nonrelativistic ones in the limit Applications to experiments with the scanning probe microscopes, quartz crystal microbalance technique and transmission of particle beams in the near field of surfaces (through nanochannels) are discussed.

cond-mat.mes-hall↗
arXiv2011

Dynamical van der Waals atom -surface interaction

We obtained new nonrelativistic expression for the dynamical van der Waals atom -surface interaction energy of very convenient form for different applications. It is shown that classical result (Ferrell and Ritchie, 1980) holds only for a very slowly moving atom. In general case, the van der Waals atom -surface interaction energy manifests strong nonlinear dependence on velocity and distance. In close vicinity of metal and dielectric surfaces and velocities from 1 to 10 Bohr units the dynamical van der Waals potential proves to be significantly lower that in static case and goes to the static values with increasing distance and (or) decreasing velocity.

cond-mat.other↗
arXiv2011

Tangential and quantum frictional forces on a neutral particle moving near a surface

We calculate tangential forces applied to a ground state atom (nanoparticle) moving with nonrelativistic velocity parallel to the surface of Drude -modelled or Lorentz -modelled half -space using the formalism of fluctuation electrodynamics.The obtained formulae assume the nonretarded regime and arbitrary temperatures of the particle and medium. The quantum frictional force is realized at zero temperature of the particle and medium and can reach about 1/3 of the static value of the Casimir -Polder force in the case of ground state atom. In the case of nanoparticles and nonzero temperature, the tangential forces appears to be both frictional and accelerating. Numerical examples are given for atoms of Na above the surface of Au and MgO nanoparticles above the surface of SiC.

cond-mat.other↗
arXiv2010

Radiative heat exchange of spherical particles with metal and insulator plates

Radiative heat exchange of spherical particles between each other and with thick polarizable plates is studied in the framework of fluctuation electrodynamics. An additive dipole approximation for the thermal conductance of micrometer sized particles is proposed. The numerical calculations are performed for particles and plates made of gold and silica. Several theoretical models of radiative conductance are compared and juxtaposed with the known experimental data.

cond-mat.other↗
arXiv2009

Tangential force and heating rate of a neutral relativistic particle mediated by equilibrium background radiation

A relativistic theory of fluctuation -electromagnetic interaction of a small polarizable particle moving with respect to the equilibrium background radiation is reviewed. It is assumed that the particle radius is smaller then characteristic wave length of the background radiation. General relativistic relations for the particle heating rate and tangential force are obtained and compared with nonrelativistic and relativistic expressions of other authors.

physics.class-ph↗
arXiv2009

Conservative-dissipative forces and heating mediated by fluctuation electromagnetic field: two plates in relative nonrelativistic motion

We calculate heating rate, attractive conservative and tangential dissipative fluctuation electromagnetic forces felt by a thick plate moving with nonrelativistic velocity parallel to a closely spaced another plate in rest using relativistic fluctuation electrodynamics. We argue that recently developed relativistic out of equilibrium theory of fluctuation electromagnetic interactions (Volokitin et. al., Phys.Rev. B78, 155437 (2008))has serious drawbacks.

cond-mat.other↗