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Anna S Zelenina

Publications and source records attributed to Anna S Zelenina.

10 recordsLinked to original sources
PubMed2006

Tunable optical sorting and manipulation of nanoparticles via plasmon excitation.

We numerically investigate the optical forces exerted by an incident light beam on Rayleigh metallic particles over a dielectric substrate. In analogy with atom manipulation, we identify two different trapping regimes depending on whether the illumination is performed within the plasmon band or out of it. By adjusting the incident wavelength, the particles can be selectively guided, or immobilized, at the substrate interface.

Dose-Response Relationship, Radiation↗
PubMed2004

Stabilization of vector solitons in optical lattices.

We address the properties and dynamical stability of one-dimensional vector lattice solitons in a Kerr-type cubic medium with harmonic transverse modulation of the refractive index. We discovered that unstable families of scalar lattice solitons can be stabilized via cross-phase modulation (XPM) in the vector case. It was found that multihumped vector solitons that are unstable in uniform media where the XPM strength is higher than that of self-phase modulation can also be stabilized by the lattice.

Journal Article↗
PubMed2004

Soliton eigenvalue control in optical lattices.

We address the dynamics of higher-order solitons in optical lattices, and predict their self-splitting into the set of their single-soliton constituents. The splitting is induced by the potential introduced by the lattice, together with the imprinting of a phase tilt onto the initial multisoliton states. The phenomenon allows the controllable generation of several coherent solitons linked via their Zakharov-Shabat eigenvalues. Application of the scheme to the generation of correlated matter waves in Bose-Einstein condensates is discussed.

Journal Article↗
PubMed2004

Spatial soliton switching in quasi-continuous optical arrays.

We report on the phenomenon of trapping and switching of one-dimensional spatial solitons in Kerr-type nonlinear media with transverse periodic modulation of the refractive index. The solitons slowly radiate upon propagation along the periodic structure and are finally trapped in one of its guiding channels. The position of the output channel can be varied by small changes in the launching angle.

Journal Article↗
PubMed2004

Stable multicolor periodic-wave arrays.

We study the existence and stability of periodic-wave arrays propagating in uniform quadratic nonlinear media and discover that they become completely stable above a threshold light intensity. To the best of our knowledge, this is the first example in physics of completely stable periodic-wave patterns propagating in conservative uniform media supporting bright solitons.

Journal Article↗
PubMed2003

Stabilization of one-dimensional periodic waves by saturation of the nonlinear response.

We address the properties of (1+1)-dimensional periodic waves in conservative saturable cubic nonlinear media and discover that cnoidal- and snoidal-type waves are completely stable within a broad range of parameters. The existence of stability bands is in sharp contrast with the previously known properties of periodic waves in self-focusing Kerr nonlinear media. We also found that in self-defocusing media instability bands occur, again in contrast to the case of Kerr media.

Journal Article↗
PubMed2003

Metastability of dark snoidal-type waves in quadratic nonlinear media.

We report the existence and basic properties of dark snoidal-type waves self-sustained in quadratic nonlinear media. Using a stability analysis technique, we reveal that they are almost completely stable, or metastable, in suitable ranges of input energy flows and material parameters. This opens the way to the experimental observation of dark-type multicolor periodic wave patterns supported by quadratic nonlinearities.

Journal Article↗
PubMed2003

Stability analysis of spatiotemporal cnoidal waves in cubic nonlinear media.

We analyze numerically the modulational instability of spatiotemporal cnoidal waves of cn, dn, and sn types that are periodic along a single space coordinate and are uniform in time. The band of possible increments is calculated for all three types of cnoidal waves as a function of parameter describing the degree of localization of the wave field energy. It is shown that this band transforms into a set of discrete values for waves of cn and dn types in the limit of strong spatial localization. Simulation of perturbed cnoidal-wave propagation revealed suppression of collapse and multiple-wave filamentation on the developed stage of instability. Different instability scenarios are considered in detail.

Journal Article↗
PubMed2003

Stability analysis of (1+1)-dimensional cnoidal waves in media with cubic nonlinearity.

In the present paper we perform stability analysis of stationary (1+1)-dimensional cnoidal waves of cn and dn types (anomalous group velocity dispersion) and sn type (normal group velocity dispersion). The mathematical model is based on the nonlinear Schrödinger equation. With this aim we developed a method that takes into consideration the properties of complex eigenvalues of Cauchy matrix for perturbation vectors. We show that cnoidal sn-wave is stable in the whole domain of its existence, whereas cn- and dn-waves are unstable. The instability of cn- and dn-waves is suppressed in the limiting case of strong localization when waves evolve into a set of well-separated fundamental bright solitons.

Journal Article↗