Theoretical model of temperature dynamics of solid surface of material under action of laser radiation

We have developed a theoretical model that describes the interaction of intense pulsed flows of energy with matter and is based on the account of local phase transitions at the destruction of a surface. In the frame of a problem concerning the influence of a laser radiation on the surface prior to the beginning of the solid surface destruction, we have solved the equation for the energy flow. The general solution of the equation for the temperature change of a local area of the irradiated solid surface in time is obtained with regard for the coefficient of surface dissipative losses and the volume absorption coefficient. It is shown that the temperature dynamics stimulated by the intense laser radiation depends substantially on properties of the surface layer of the irradiated material

The effect of the dynamic splitting of the conductivity state in homogeneous electric field

The features of a completely homogeneous external electrostatic field effect on the properties of a quasiparticle of the electron type injected into the conduction band of a semiconductor or dielectric are considered. As applied to this case (completely homogeneous external field), the equations obtained earlier are analyzed, which provide a consistent quantum (basic) and classical (in terms of quasiparticles) descriptions. It is shown that these equations reflect regularities that do not allow the "direct" application of the external field both in the basic (quantum) and in the effective (in terms of quasiparticles) descriptions. These regularities and the corresponding equations are one of the possible causes for the experimentally observed anomalous splitting of the conductivity state in strong fields. In the article this splitting was called a dynamic splitting. A satisfactory agreement with the experiment was obtained

Features of generalized dynamics of quasiparticles in the presence of an external potential field. Part 2. Minkowski equations and degeneration of mobility in the strong fields

This article analyses the influence of the external electrostatic field (having an arbitrary space configuration) upon the properties of a free quasi-particle (for example, on the properties of the electron, which was injected into a semiconductor or into a dielectric). Approximations were formulated, that ensure fulfilment of the generalized Minkowski equations for the components of the external field for both methods of description: a quantum method of description within a local frame of reference and a classic method of description within a global frame of reference. It was demonstrated that the generalized dynamics of a quasiparticle in the external potential field might be one of the possible reasons of the abnormal mobility of carriers in the strong fields

Degeneracy effect of dynamical properties of quasi-particles of electronic origin in semiconductor materials

The general dynamical properties of free quasi-particles are analyzed. Analyzed also the conditions under which the description of the dynamic properties of the quasi-particles is almost identical with those of real relativistic particles. The problem of the relation of quantum and classical methods of describing the quasi-particles in the case of the excited states of crystals is considered. Basic principles of construction of dynamic properties of classic type for quasi-particles at excitation of matter with the structure of solids (crystals) are analyzed. The results of analysis were demonstrated on the example of electronic excitations of crystals in the simplest case, when other effects are neglected (phonons, the response to excitation of the lattice, defects, high density of excitations, which requires the account of interactions between them, and so forth). It was shown that such excitations are described in three ways simultaneously. These descriptions make it possible to interpret the experimental data in terms of the usual relativistic dynamics, if the considered system allows the use of the considered approximations (plane wave in a phase, nearest neighbors and cubic grate)

Features of generalized dynamics of quasiparticles in the presence of an external potential field. Part 1. General analysis of the problem

The influence of the external field (electrostatic) of an arbitrary spatial configuration on the common dynamic properties of the free quasiparticle of type of injecting in the semiconductor or dielectric electron is examined. In the quasi-linear approximation with respect to the external field and in the generalized approximation of flat wave in the phase of wave function the completely agreement of simultaneous quantum description (basic) and a description of the classical type (for the dynamics of quasiparticle) is possible. Correlations, which save determinations of basic dynamic characteristics of quasiparticle the same as they are in the absence of an external field established also

The centrally-symmetric solutions of electronic excitations of semiconductors in the conditions of relativistic like degeneracy of dynamical properties

The excited states of materials with the structure of crystals were analyzed in the paper. Here the reaction of crystalline lattice on excitation was taken into account. Such consideration leads to nonlinear Schredinger equations. At a solution of these equations some possible variants of the nonlinearities which are different from the cubic are considered. The possibility of constructing of spherically-symmetric analytical solutions with finite norm analyzed. The analytical solutions in the form of centrally symmetric solitons were found. The obtained solutions show the expressed wave-corpuscle dualism. It is shown, that dynamic properties of excitation are identical to dynamics of not self-trapped quasiparticle. An important feature of these solutions is that their amplitudes (or squares of the amplitudes) have an asymptotic behavior of the type of 1/ρ, with ρ →∞