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Doskolovich, L L

Publications and source records attributed to Doskolovich, L L.

Resonant diffraction gratings for spatial differentiation of optical beams

Diffraction of a two-dimensional optical beam from a resonant diffraction grating is considered. It is shown that at certain resonance parameters the diffraction grating allows for spatial differentiation and integration of the incident beam. The parameters of the diffraction grating for spatial differentiation of optical beams in the transmission geometry are calculated. It is shown that the differentiating diffraction grating allows the conversion of the two-dimensional beam into the two-dimensional Hermite – Gaussian mode. The presented results of numerical modelling are in good agreement with the proposed theoretical description. The use of the considered resonant diffraction gratings is promising for solving the problems of all-optical data processing. (laser applications and other topics in quantum electronics)

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

On the ability of resonant diffraction gratings to differentiate a pulsed optical signal

The passage of an optical pulse through a resonant grating is considered. The conditions under which the resonant grating differentiates the envelope of the incident pulse are determined. It is shown that the necessary condition for computing the k-order derivative is the presence of k resonances in the transmission spectrum of the grating in the vicinity of the central frequency of the incident pulse. A method is described for constructing the stacked structure for computing the kth derivative on the basis of repetition of the structure for computing the first derivative. The results of numerical simulation of diffraction of the pulse from the analyzed structure for computing the first, second, and third derivative are presented.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

Interference pattern generation in evanescent electromagnetic waves for nanoscale lithography using waveguide diffraction gratings

The generation of interference patterns of evanescent electromagnetic waves with an essentially subwavelength period using dielectric waveguide diffraction gratings is considered. Using simulations within the framework of the electromagnetic theory, the possibility of obtaining high-quality interference patterns due to enhancement of evanescent diffraction orders under resonance conditions is demonstrated. The contrast of the interference patterns in the case of TE polarisation of the incident wave is close to unity. The field intensity in the near-field interference maxima exceeds the intensity of the incident wave by 25-100 times. The possibility of generation of the interference patterns of evanescent waves corresponding to higher diffraction orders is shown. The use of higher orders reduces the requirements to the fabrication technology and allows generation of interference patterns with a high spatial frequency, using diffraction gratings with a low spatial frequency. Examples of generating interference patters with periods six times smaller than those of the used diffraction gratings are presented. (nanolithography)

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗