The results of both analytical and numerical calculations of the light scattering by periodic arr... more The results of both analytical and numerical calculations of the light scattering by periodic array (either finite or infinite) of gold nanocylinders are compared. Surprisingly, the dipole approximation appears to be well applicable down to the distance between the cylinders only twice exceeding their diameter.
The scattering of electromagnetic wave by a periodic array of nanowires is calculated by the boun... more The scattering of electromagnetic wave by a periodic array of nanowires is calculated by the boundary element method. The method is extended to the infinite grating near the interface between two dielectrics. A special Green function is derived that allows to study the evanescent wave. The Rayleigh--- Wood's anomalies are found in the period-to-wavelength dependence of the average Pointing vector in the wave zone. For thin wires the calculations are shown to agree with the two-dimensional coupled dipole approximation.
Proceedings of Spie the International Society For Optical Engineering, Oct 1, 1998
The applications of the new interferometric techniques to the measurement of nonlinear refractive... more The applications of the new interferometric techniques to the measurement of nonlinear refractive index are summarized in this paper. Developed methods are based on dispersion and shearing interferometry and allow to perform the direct phase measurements in the near field. The majority of the limitations of traditional interferometers have been eliminated in these schemes. At the same time, the benefit of using these methods comparable to currently used is shown for the cases of complicated dependence of the refractive index on the intensity and when the response time of nonlinearity is comparable with the laser pulse duration.
Proceedings of Spie the International Society For Optical Engineering, Apr 1, 2007
The light-induced forces in the aggregates of metal nanoparticles are studied with the Newton's a... more The light-induced forces in the aggregates of metal nanoparticles are studied with the Newton's and coupled dipole equations. The simulations imply a linear intrinsic optical response of the particles and host medium. Large and relatively fast third-order optical nonlinearity of such a nanocomposite is shown to originate from the light-induced motion of the particles. The nonlinear absorption coefficients of an artificial medium composed of 5-particles aggregates are simulated at different intensities and frequencies of the incident light. The calculated nonlinear absorption appears to be of the same order of magnitude as typically measured for the silver colloids.
The new mechanism for obtaining a nonlinear phase shift has been proposed and the schemes are des... more The new mechanism for obtaining a nonlinear phase shift has been proposed and the schemes are described for its implementation. As it is shown, the interference of two waves with intensity-dependent amplitude ratio coming from the second harmonic generation should produce the nonlinear phase shift. The sign and amount of nonlinear distortion of a beam wavefront is dependent of the relative phase of the waves that is introduced by the phase element. Calculated value of $n_2^{eff}$ exceeds that connected with cascaded quadratic nonlinearity, at the same conditions.
The results of both analytical and numerical calculations of the light scattering by periodic arr... more The results of both analytical and numerical calculations of the light scattering by periodic array (either finite or infinite) of gold nanocylinders are compared. Surprisingly, the dipole approximation appears to be well applicable down to the distance between the cylinders only twice exceeding their diameter.
The scattering of electromagnetic wave by a periodic array of nanowires is calculated by the boun... more The scattering of electromagnetic wave by a periodic array of nanowires is calculated by the boundary element method. The method is extended to the infinite grating near the interface between two dielectrics. A special Green function is derived that allows to study the evanescent wave. The Rayleigh--- Wood's anomalies are found in the period-to-wavelength dependence of the average Pointing vector in the wave zone. For thin wires the calculations are shown to agree with the two-dimensional coupled dipole approximation.
Proceedings of Spie the International Society For Optical Engineering, Oct 1, 1998
The applications of the new interferometric techniques to the measurement of nonlinear refractive... more The applications of the new interferometric techniques to the measurement of nonlinear refractive index are summarized in this paper. Developed methods are based on dispersion and shearing interferometry and allow to perform the direct phase measurements in the near field. The majority of the limitations of traditional interferometers have been eliminated in these schemes. At the same time, the benefit of using these methods comparable to currently used is shown for the cases of complicated dependence of the refractive index on the intensity and when the response time of nonlinearity is comparable with the laser pulse duration.
Proceedings of Spie the International Society For Optical Engineering, Apr 1, 2007
The light-induced forces in the aggregates of metal nanoparticles are studied with the Newton's a... more The light-induced forces in the aggregates of metal nanoparticles are studied with the Newton's and coupled dipole equations. The simulations imply a linear intrinsic optical response of the particles and host medium. Large and relatively fast third-order optical nonlinearity of such a nanocomposite is shown to originate from the light-induced motion of the particles. The nonlinear absorption coefficients of an artificial medium composed of 5-particles aggregates are simulated at different intensities and frequencies of the incident light. The calculated nonlinear absorption appears to be of the same order of magnitude as typically measured for the silver colloids.
The new mechanism for obtaining a nonlinear phase shift has been proposed and the schemes are des... more The new mechanism for obtaining a nonlinear phase shift has been proposed and the schemes are described for its implementation. As it is shown, the interference of two waves with intensity-dependent amplitude ratio coming from the second harmonic generation should produce the nonlinear phase shift. The sign and amount of nonlinear distortion of a beam wavefront is dependent of the relative phase of the waves that is introduced by the phase element. Calculated value of $n_2^{eff}$ exceeds that connected with cascaded quadratic nonlinearity, at the same conditions.
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Papers by Sergey Perminov