A. K. Sukhorukova

Diffraction of optical waves by nonlinearly induced cylinders

The diffraction of optical waves by transparent and opaque cylinders formed by laser beams in defocusing nonlinear media has been investigated for the first time. The wave flow around a single beam (cylinder) and wave signal percolation through the slits formed by closely spaced laser beams have been numerically modeled.

Cascaded induced lattices in quadratic nonlinear medium

We first study features of optical periodic lattices generated with mismatched cascade three-wave interaction in quadratically nonlinear media. We elaborate the theory of parametric waveguides arrays induced by two crossing pump waves together with exited sum wave. As the signal wave spreads due to the diffraction the induced lattice appears and its transverse dimension increases. Note the parametric periodic grating becomes apparent since launching any signal beam. Its likely to be the leading peculiarity of cascaded induced lattices. Parametric inhomogeneity depends on wave vector mismatch sign, and its modulation depth can be controlled by pump beam intensity. We observed a transformation from the discrete diffraction into the waveguiding of one or several signal beams with the increasing of pump intensity. The discrete diffraction dynamics dependence on pump intensity, spatial period, and signal beam tilting is analyzed when one or few central waveguides are exited at the input. At the certain incidence diffractionless propagation of signal beam takes place. The similar discrete diffraction effects in 2D cascaded lattices with various pump structure geometries have been studied. The additional degree of freedom gives novel properties to the effect of discrete diffraction.

Optical parametric oscillators with phase-modulated pumping

The dynamics of emission from two- and one-resonator optical parametric oscillators is analyzed for phase-modulated pump pulses. The time dependences of the envelope and instantaneous frequency of a pulse emitted by an optical parametric oscillator are considered. The analysis is made using differential equations for the complex amplitudes of the field, obtained from the difference equations which occur in the step method if the single-pass gain is small.