K. V. Rudenko

Adiabatic Interaction between a Dark Soliton and a Cnoidal Wave with Orthogonal Circular Polarizations in an Isotropic Gyrotropic Nonlinear Medium

An analytical solution to the one-dimensional (plane waves) nonintegrable problem of interaction (collision) of a dark soliton with a cnoidal wave (control and information signals with orthogonal circular polarizations) in an isotropic gyrotropic medium with Kerr nonlinearity and second-order groupvelocity dispersion is obtained in the adiabatic approximation. The asymptotic behavior of the obtained solution is considered. It is shown that the role of the control signal is reduced to strong amplitude and frequency modulation, which is localized only in the region of variation in the control signal intensity.

Training of photorefractive self-pumped phase-conjugate mirrors

We show the speed of response of a photorefractive self-pumped phase-conjugate mirror can be considerably (6 - 20 times) accelerated by special training procedures. Efficiency of some such procedures is compared and analyzed.

Training of self-pumped phase-conjugate mirrors based on photorefractive nonlinearity

In the paper we will show that formation of a phase-conjugated wave in a self-pumped phase-conjugate mirror can be considerably (6 - 20 times faster) accelerated by a special training procedure. Efficiency of some static and dynamic training procedures will be compared and analyzed.

Phase-conjugation dynamics in self-pumping photorefractive loop mirrors

Dynamics of self-pumping photorefractive loop mirrors will be considered. We will show that depending on experimental conditions as phase-conjugation with efficiency up to 70-80% as formation of unstable oscillating structures of soliton-like filaments can be realized.

Dynamics of self-pumping photorefractive double phase-conjugate mirrors

Dynamics of self-pumping photorefractive double phase-conjugate mirrors is considered. It is shown that depending on experimental conditions as phase-conjugation with efficiency up to 60-80 % as formation of unstable structures of soliton-like filaments can be realized.

Long-living meta-stable non-equilibrium states of HTSC compounds in transient four-photon spectroscopy

It will be shown that experimental data, obtained by pump-probe measurements in HTSC compounds, can be interpreted in terms of long-living meta-stable non-equilibrium states with specific energy gap and rather high (up to 600 K) electronic temperature.

Writing the regular domain structures in ultra-thin ferromagnetic films by short trains of ultra-short laser pulses

A new laser technology, based on spatiallyl non-uniform illumination of ultra-thin ferromagnetic films by short trains of ultra-short laser pulses and enabling to create the regular domain structures, is presented.

Ultrafast cooling of electronic subsystem in ultrathin metal films

On the basis of experimental data of degenerate four-photon spectroscopy of Ni, Au and Pt ultra-thin (with the thickness approximately 10 divided by 20 nm) films, a conclusion about a predominant role of inter-band electronic transitions under formation of a nonlinear response of such films in the visible range has been made. It has been shown that, when a metal film thickness is smaller than the mean-free path, thermalization and cooling of optically excited electronic subsystem result from an ultra-fast inelastic scattering of excess free carriers on the film surface. Numerical estimations, performed for ultra-thin Ni films, have shown that, thanks to this scattering process, up to 10% of picosecond (duration approximately 20 ps) pump pulse energy can be transformed to the surface deformations. In case of spatially non-uniform optical excitation, an efficient direct generation of the surface acoustical waves can be realized.