236 research outputs found
Role of Community Informatics in Socio-Cultural Transformations in Russia and the CIS
Role of Community Informatics in Socio-Cultural Transformations in Russia and the CI
Indexing of Computer Optics in the Emerging Sources Citation Index database
Inclusion of the journal Computer Optics in the Emerging Sources Citation Index database is described in this editorial
Tight focusing of azimuthally polarized optical vortex produced by subwavelength grating
Focusing of an optical vortex with sectorial azimuthal polarization is numerically investigated. An effect of sector numbers on the results of focusing is estimated. It is shown that the focal spot produced by a beam with six sectors does not differ from the ideally azimuthally polarized optical vortex; a difference in the focal spot diameter does not exceed 0.001 of the wavelength. For a four-sectoral beam, the difference does not exceed 0.028 of the wavelength. We have investigated a four-Sector transmission Polarization Converter for a wavelength of 633 nm, that enables the conversion of a linearly polarized incident beam into a mixture of linearly and azimuthally polarized beams. It was experimentally shown that light propagated through the four-Sector transmission Polarization Converter and focused by Fresnel zone plate with a focal length of 532 nm produces focal spot with diameters 0.46 and 0.57 of wavelength.Publisher PD
Estimating the scale of stone axe production: A case study from Onega Lake, Russian Karelia
The industry of metatuff axes and adzes on the western coast of Onega Lake (Eneolithic period, ca. 3500 β 1500 cal. BC) allows assuming some sort of craft specialization. Excavations of a workshop site Fofanovo XIII, conducted in 2010-2011, provided an extremely large assemblage of artefacts (over 350000 finds from just 30 m2, mostly production debitage). An attempt to estimate the output of production within the excavated area is based on experimental data from a series of replication experiments. Mass-analysis with the aid of image recognition software was used to obtain raw data from flakes from excavations and experiments. Statistical evaluation assures that the experimental results can be used as a basement for calculations. According to the proposed estimation, some 500 β 1000 tools could have been produced here, and this can be qualified as an evidence of βmass-productionβ
Subwavelength grating-based spiral metalens for tight focusing of laser light
In this paper, we investigate a 16-sector spiral metalens fabricated on a thin film (130 nm) of amorphous silicon, consisting of a set of subwavelength binary diffractive gratings and with a numerical aperture that is close to unity. The metalens converts linearly polarized incident light into an azimuthally polarized optical vortex and focuses it at a distance approximately equal to the wavelength of the incident light, k ΒΌ 633 nm. Using a scanning near-field optical microscope, it is shown experimentally that the metalens forms an elliptical focal spot with diameters smaller than the diffraction limit: FWHMx ΒΌ 0.32k (60.03k) and FWHMy ΒΌ 0.51k (60.03k). The experimental results are close to those of a numerical simulation using the FDTD method, with FWHMx ΒΌ 0.37k and FWHMy ΒΌ 0.49k. The technological errors due to manufacturing were taken into account in the simulation. This is the smallest focal spot yet obtained with a metalens
Subwavelength micropolarizer in a gold film for visible light
Engineering and Physical Sciences Research Council (EPSRC) (EP/L017008/1); European Research Council (337508); Russian Foundation for Basic Research (RFBR) (14-07-97039, 14-29-07133, 15-07-01174, 15-37-20723, 16-07-00990, 16-29-11698); Ministry of Education and Science of the Russian Federation (MK-9019.2016.2).We have designed and fabricated a 100 ΞΌm x 100 ΞΌm four-sector binary subwavelength reflecting polarization microconverter in a gold film. Using finite-difference time-domain-aided numerical simulations and experiments, the micropolarizer was shown to convert an incident linearly polarized Gaussian beam of wavelength 532 nm into an azimuthally polarized beam. Conditions for generating on-axis regions of nonzero intensity when using propagating optical vortices with different initial polarization were deduced. By putting a spiral phase plate into an azimuthally polarized beam, the intensity pattern was shown to change from diffraction rings to a central peak.PostprintPeer reviewe
A transverse energy flow at the tight focus of light with higher-order circular-azimuthal polarization
Π Π°ΡΡΠΌΠΎΡΡΠ΅Π½Π° ΠΎΡΡΡΠ°Ρ ΡΠΎΠΊΡΡΠΈΡΠΎΠ²ΠΊΠ° ΡΠ²Π΅ΡΠ° Ρ ΡΠΈΡΠΊΡΠ»ΡΡΠ½ΠΎ-Π°Π·ΠΈΠΌΡΡΠ°Π»ΡΠ½ΠΎΠΉ ΠΏΠΎΠ»ΡΡΠΈΠ·Π°ΡΠΈΠ΅ΠΉ m-Π³ΠΎ ΠΏΠΎΡΡΠ΄ΠΊΠ°. ΠΡΠΎ Π½ΠΎΠ²ΡΠΉ ΡΠΈΠΏ Π½Π΅ΠΎΠ΄Π½ΠΎΡΠΎΠ΄Π½ΠΎΠΉ Π³ΠΈΠ±ΡΠΈΠ΄Π½ΠΎΠΉ ΠΏΠΎΠ»ΡΡΠΈΠ·Π°ΡΠΈΠΈ, ΠΎΠ±ΡΠ΅Π΄ΠΈΠ½ΡΡΡΠΈΠΉ ΡΠ²ΠΎΠΉΡΡΠ²Π° ΡΠΈΠ»ΠΈΠ½Π΄ΡΠΈΡΠ΅ΡΠΊΠΎΠΉ ΠΏΠΎΠ»ΡΡΠΈΠ·Π°ΡΠΈΠΈ m-Π³ΠΎ ΠΏΠΎΡΡΠ΄ΠΊΠ° ΠΈ ΠΊΡΡΠ³ΠΎΠ²ΠΎΠΉ ΠΏΠΎΠ»ΡΡΠΈΠ·Π°ΡΠΈΠΈ. Π‘ ΠΏΠΎΠΌΠΎΡΡΡ ΡΠΎΡΠΌΠ°Π»ΠΈΠ·ΠΌΠ° Π ΠΈΡΠ°ΡΠ΄ΡΠ°βΠΠΎΠ»ΡΡΠ° ΠΏΠΎΠ»ΡΡΠ΅Π½Ρ Π°Π½Π°Π»ΠΈΡΠΈΡΠ΅ΡΠΊΠΈΠ΅ Π²ΡΡΠ°ΠΆΠ΅Π½ΠΈΡ Π² ΡΠΎΠΊΡΡΠ΅ Π΄Π»Ρ ΠΏΡΠΎΠ΅ΠΊΡΠΈΠΉ Π²Π΅ΠΊΡΠΎΡΠΎΠ² Π½Π°ΠΏΡΡΠΆΠ΅Π½Π½ΠΎΡΡΠΈ ΡΠ»Π΅ΠΊΡΡΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ ΠΈ ΠΌΠ°Π³Π½ΠΈΡΠ½ΠΎΠ³ΠΎ ΠΏΠΎΠ»Π΅ΠΉ, ΡΠ°ΡΠΏΡΠ΅Π΄Π΅Π»Π΅Π½ΠΈΡ ΠΈΠ½ΡΠ΅Π½ΡΠΈΠ²Π½ΠΎΡΡΠΈ, ΠΏΡΠΎΠ΅ΠΊΡΠΈΠΉ Π²Π΅ΠΊΡΠΎΡΠ° ΠΠΎΠΉΠ½ΡΠΈΠ½Π³Π° ΠΈ ΡΠΏΠΈΠ½ΠΎΠ²ΠΎΠ³ΠΎ ΡΠ³Π»ΠΎΠ²ΠΎΠ³ΠΎ ΠΌΠΎΠΌΠ΅Π½ΡΠ°. Π’Π΅ΠΎΡΠ΅ΡΠΈΡΠ΅ΡΠΊΠΈ ΠΈ ΡΠΈΡΠ»Π΅Π½Π½ΠΎ ΠΏΠΎΠΊΠ°Π·Π°Π½ΠΎ, ΡΡΠΎ ΠΈΠ½ΡΠ΅Π½ΡΠΈΠ²Π½ΠΎΡΡΡ Π² ΡΠΎΠΊΡΡΠ΅ ΠΈΠΌΠ΅Π΅Ρ 2(m+1) Π»ΠΎΠΊΠ°Π»ΡΠ½ΡΡ
ΠΌΠ°ΠΊΡΠΈΠΌΡΠΌΠΎΠ², ΡΠ°ΡΠΏΠΎΠ»ΠΎΠΆΠ΅Π½Π½ΡΡ
Π²Π΄ΠΎΠ»Ρ Π·Π°ΠΌΠΊΠ½ΡΡΠΎΠ³ΠΎ ΠΊΠΎΠ½ΡΡΡΠ° Ρ Π½ΡΠ»Π΅Π²ΠΎΠΉ ΠΈΠ½ΡΠ΅Π½ΡΠΈΠ²Π½ΠΎΡΡΡΡ Π² ΡΠ΅Π½ΡΡΠ΅ (Π½Π° ΠΎΠΏΡΠΈΡΠ΅ΡΠΊΠΎΠΉ ΠΎΡΠΈ). ΠΠΎΠΊΠ°Π·Π°Π½ΠΎ, ΡΡΠΎ Π² ΡΠΎΠΊΡΡΠ΅ ΠΈΠΌΠ΅Π΅ΡΡΡ 4m Π²ΠΈΡ
ΡΠ΅ΠΉ ΠΏΠΎΠΏΠ΅ΡΠ΅ΡΠ½ΠΎΠ³ΠΎ ΠΏΠΎΡΠΎΠΊΠ° ΡΠ½Π΅ΡΠ³ΠΈΠΈ, ΡΠ΅Π½ΡΡΡ ΠΊΠΎΡΠΎΡΡΡ
ΡΠ°ΡΠΏΠΎΠ»ΠΎΠΆΠ΅Π½Ρ ΠΌΠ΅ΠΆΠ΄Ρ Π»ΠΎΠΊΠ°Π»ΡΠ½ΡΠΌΠΈ ΠΌΠ°ΠΊΡΠΈΠΌΡΠΌΠ°ΠΌΠΈ ΠΈΠ½ΡΠ΅Π½ΡΠΈΠ²Π½ΠΎΡΡΠΈ. Π’Π°ΠΊΠΆΠ΅ ΠΏΠΎΠΊΠ°Π·Π°Π½ΠΎ, ΡΡΠΎ ΠΏΠΎΠΏΠ΅ΡΠ΅ΡΠ½ΡΠΉ ΠΏΠΎΡΠΎΠΊ ΡΠ½Π΅ΡΠ³ΠΈΠΈ ΠΌΠ΅Π½ΡΠ΅Ρ Π½Π°ΠΏΡΠ°Π²Π»Π΅Π½ΠΈΠ΅ Π²ΡΠ°ΡΠ΅Π½ΠΈΡ 2(2m+1) ΡΠ°Π·Π° ΠΏΡΠΈ ΠΎΠ±Ρ
ΠΎΠ΄Π΅ Π² ΠΏΠ»ΠΎΡΠΊΠΎΡΡΠΈ ΡΠΎΠΊΡΡΠ° Π²ΠΎΠΊΡΡΠ³ ΠΎΠΏΡΠΈΡΠ΅ΡΠΊΠΎΠΉ ΠΎΡΠΈ. ΠΠ½ΡΠ΅ΡΠ΅ΡΠ½ΠΎ, ΡΡΠΎ ΠΏΡΠΎΠ΄ΠΎΠ»ΡΠ½Π°Ρ ΠΏΡΠΎΠ΅ΠΊΡΠΈΡ ΡΠΏΠΈΠ½ΠΎΠ²ΠΎΠ³ΠΎ ΡΠ³Π»ΠΎΠ²ΠΎΠ³ΠΎ ΠΌΠΎΠΌΠ΅Π½ΡΠ° Π² ΡΠΎΠΊΡΡΠ΅ ΠΌΠ΅Π½ΡΠ΅Ρ Π·Π½Π°ΠΊ 4m ΡΠ°Π·Π°. Π ΡΠ΅Ρ
ΠΎΠ±Π»Π°ΡΡΡΡ
ΠΏΠ»ΠΎΡΠΊΠΎΡΡΠΈ ΡΠΎΠΊΡΡΠ°, Π³Π΄Π΅ ΠΏΠΎΠΏΠ΅ΡΠ΅ΡΠ½ΡΠΉ ΠΏΠΎΡΠΎΠΊ ΡΠ½Π΅ΡΠ³ΠΈΠΈ Π²ΡΠ°ΡΠ°Π΅ΡΡΡ ΠΏΡΠΎΡΠΈΠ² ΡΠ°ΡΠΎΠ²ΠΎΠΉ ΡΡΡΠ΅Π»ΠΊΠΈ, ΠΏΡΠΎΠ΄ΠΎΠ»ΡΠ½Π°Ρ ΠΏΡΠΎΠ΅ΠΊΡΠΈΡ ΡΠΏΠΈΠ½ΠΎΠ²ΠΎΠ³ΠΎ ΡΠ³Π»ΠΎΠ²ΠΎΠ³ΠΎ ΠΌΠΎΠΌΠ΅Π½ΡΠ° ΠΏΠΎΠ»ΠΎΠΆΠΈΡΠ΅Π»ΡΠ½Π°Ρ, Π° Π²Π΅ΠΊΡΠΎΡ ΠΏΠΎΠ»ΡΡΠΈΠ·Π°ΡΠΈΠΈ Π²ΡΠ°ΡΠ°Π΅ΡΡΡ Π² ΠΏΠ»ΠΎΡΠΊΠΎΡΡΠΈ ΡΠΎΠΊΡΡΠ° ΠΏΡΠΎΡΠΈΠ² ΡΠ°ΡΠΎΠ²ΠΎΠΉ ΡΡΡΠ΅Π»ΠΊΠΈ. Π Π½Π°ΠΎΠ±ΠΎΡΠΎΡ, Π³Π΄Π΅ ΠΏΠΎΡΠΎΠΊ ΡΠ½Π΅ΡΠ³ΠΈΠΈ Π²ΡΠ°ΡΠ°Π΅ΡΡΡ ΠΏΠΎ ΡΠ°ΡΠΎΠ²ΠΎΠΉ ΡΡΡΠ΅Π»ΠΊΠ΅, ΡΠ°ΠΌ ΠΈ Π²Π΅ΠΊΡΠΎΡ ΠΏΠΎΠ»ΡΡΠΈΠ·Π°ΡΠΈΠΈ Π²ΡΠ°ΡΠ°Π΅ΡΡΡ ΠΏΠΎ ΡΠ°ΡΠΎΠ²ΠΎΠΉ ΡΡΡΠ΅Π»ΠΊΠ΅, Π° ΠΏΡΠΎΠ΄ΠΎΠ»ΡΠ½Π°Ρ ΠΏΡΠΎΠ΅ΠΊΡΠΈΡ ΡΠΏΠΈΠ½ΠΎΠ²ΠΎΠ³ΠΎ ΡΠ³Π»ΠΎΠ²ΠΎΠ³ΠΎ ΠΌΠΎΠΌΠ΅Π½ΡΠ° ΠΎΡΡΠΈΡΠ°ΡΠ΅Π»ΡΠ½Π°Ρ. ΠΠΎΠ΄Π΅Π»ΠΈΡΠΎΠ²Π°Π½ΠΈΠ΅ ΠΏΠΎΠ΄ΡΠ²Π΅ΡΠΆΠ΄Π°Π΅Ρ Π²ΡΠ²ΠΎΠ΄Ρ ΡΠ΅ΠΎΡΠΈΠΈ.
Tight focusing of light with mth-order circular-azimuthal polarization was investigated. This is a new type of inhomogeneous hybrid polarization that combines the properties of mth order cylindrical polarization and circular polarization. Using the Richards-Wolf formalism, we obtained analytical expressions in the focal spot for the projections of the electric and magnetic field, the intensity distribution, the projections of the Poynting vector, and the spin angular momentum. It was shown theoretically and numerically that at the focus, the intensity has 2(m+1) local maxima located on a circle centered on an on-axis intensity null. It was shown that 4m vortices of a transverse energy flow were produced at the focus, with their centers located between the local intensity maxima. It was also shown that in the focal plane, the transverse energy flow changes the direction of rotation 2(2m+1) times around the optical axis. It is interesting that the longitudinal projection of the spin angular momentum at the focus changes sign 4m times. In those areas of the focal plane where the transverse energy flow rotates counterclockwise, the longitudinal projection of the spin angular momentum is positive, and the polarization vector rotates counterclockwise in the focal plane. Conversely, if the energy flow rotates clockwise, the polarization vector rotates clockwise, and the longitudinal projection of the spin angular momentum is negative. Numerical simulations are in agreement with the theoretical investigation.Π Π°Π±ΠΎΡΠ° Π²ΡΠΏΠΎΠ»Π½Π΅Π½Π° ΠΏΡΠΈ ΠΏΠΎΠ΄Π΄Π΅ΡΠΆΠΊΠ΅ ΠΠΈΠ½ΠΈΡΡΠ΅ΡΡΡΠ²Π° Π½Π°ΡΠΊΠΈ ΠΈ Π²ΡΡΡΠ΅Π³ΠΎ ΠΎΠ±ΡΠ°Π·ΠΎΠ²Π°Π½ΠΈΡ Π² ΡΠ°ΠΌΠΊΠ°Ρ
Π²ΡΠΏΠΎΠ»Π½Π΅Π½ΠΈΡ ΡΠ°Π±ΠΎΡ ΠΏΠΎ ΠΠΎΡΡΠ΄Π°ΡΡΡΠ²Π΅Π½Π½ΠΎΠΌΡ Π·Π°Π΄Π°Π½ΠΈΡ Π€ΠΠΠ¦ Β«ΠΡΠΈΡΡΠ°Π»Π»ΠΎΠ³ΡΠ°ΡΠΈΡ ΠΈ ΡΠΎΡΠΎΠ½ΠΈΠΊΠ°Β» Π ΠΠ Π² ΡΠ°ΡΡΡΡ
Β«ΠΠ²Π΅Π΄Π΅Π½ΠΈΠ΅Β» ΠΈ Β«ΠΠ°ΠΊΠ»ΡΡΠ΅Π½ΠΈΠ΅Β», Π ΠΎΡΡΠΈΠΉΡΠΊΠΎΠ³ΠΎ Π½Π°ΡΡΠ½ΠΎΠ³ΠΎ ΡΠΎΠ½Π΄Π° (Π³ΡΠ°Π½Ρ β 18-19-00595) Π² ΡΠ°ΡΡΠΈ Β«Π Π΅Π·ΡΠ»ΡΡΠ°ΡΡ ΠΌΠΎΠ΄Π΅Π»ΠΈΡΠΎΠ²Π°Π½ΠΈΡ ΡΠΎΠΊΡΡΠΈΡΠΎΠ²ΠΊΠΈ ΡΠ²Π΅ΡΠ° Ρ Π³ΠΈΠ±ΡΠΈΠ΄Π½ΠΎΠΉ ΠΏΠΎΠ»ΡΡΠΈΠ·Π°ΡΠΈΠ΅ΠΉΒ», Π ΠΎΡΡΠΈΠΉΡΠΊΠΎΠ³ΠΎ ΡΠΎΠ½Π΄Π° ΡΡΠ½Π΄Π°ΠΌΠ΅Π½ΡΠ°Π»ΡΠ½ΡΡ
ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΠΉ Π Π€Π€Π (Π³ΡΠ°Π½Ρ β 18-29-20003) Π² ΡΠ°ΡΡΠΈ Β«ΠΠ½ΡΠ΅Π½ΡΠΈΠ²Π½ΠΎΡΡΡ ΡΠ²Π΅ΡΠ° Ρ Π³ΠΈΠ±ΡΠΈΠ΄Π½ΠΎΠΉ ΠΏΠΎΠ»ΡΡΠΈΠ·Π°ΡΠΈΠ΅ΠΉ Π² ΡΠΎΠΊΡΡΠ΅Β»)
The photonic nanojets formation by two-dimensional microprisms
Π‘ ΠΏΠΎΠΌΠΎΡΡΡ ΠΌΠ΅ΡΠΎΠ΄Π° ΠΊΠΎΠ½Π΅ΡΠ½ΡΡ
ΡΠ»Π΅ΠΌΠ΅Π½ΡΠΎΠ², ΡΠ΅Π°Π»ΠΈΠ·ΠΎΠ²Π°Π½Π½ΠΎΠ³ΠΎ Π² ΠΏΡΠΎΠ³ΡΠ°ΠΌΠΌΠ½ΠΎΠΌ ΠΏΠ°ΠΊΠ΅ΡΠ΅ COMSOL Multiphysics, ΡΠΈΡΠ»Π΅Π½Π½ΠΎ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π»Π°ΡΡ ΡΠΎΠΊΡΡΠΈΡΠΎΠ²ΠΊΠ° Π»Π°Π·Π΅ΡΠ½ΠΎΠ³ΠΎ ΠΈΠ·Π»ΡΡΠ΅Π½ΠΈΡ Π΄ΠΈΡΠ»Π΅ΠΊΡΡΠΈΡΠ΅ΡΠΊΠΈΠΌΠΈ ΠΏΡΠΈΠ·ΠΌΠ°ΠΌΠΈ Ρ ΡΡΠ΅ΡΠ³ΠΎΠ»ΡΠ½ΡΠΌ ΠΏΡΠΎΡΠΈΠ»Π΅ΠΌ. ΠΡΠ»ΠΎ ΠΏΠΎΠΊΠ°Π·Π°Π½ΠΎ, ΡΡΠΎ Π΄Π²ΡΠΌΠ΅ΡΠ½ΡΠ΅ ΡΡΠ΅ΡΠ³ΠΎΠ»ΡΠ½ΡΠ΅ ΠΏΡΠΈΠ·ΠΌΡ ΠΏΠΎΠ·Π²ΠΎΠ»ΡΡΡ ΡΠΎΠΊΡΡΠΈΡΠΎΠ²Π°ΡΡ ΡΠ²Π΅Ρ Π² ΡΠ²ΠΎΠ±ΠΎΠ΄Π½ΠΎΠΌ ΠΏΡΠΎΡΡΡΠ°Π½ΡΡΠ²Π΅ Π² ΠΏΡΡΠ½Π° Ρ ΡΠ°Π·ΠΌΠ΅ΡΠ°ΠΌΠΈ ΠΌΠ΅Π½ΡΡΠ΅ ΡΠΊΠ°Π»ΡΡΠ½ΠΎΠ³ΠΎ Π΄ΠΈΡΡΠ°ΠΊΡΠΈΠΎΠ½Π½ΠΎΠ³ΠΎ ΠΏΡΠ΅Π΄Π΅Π»Π°. ΠΠ°ΠΏΡΠΈΠΌΠ΅Ρ, ΠΏΡΠΈΠ·ΠΌΠ° ΠΈΠ· ΠΊΠ²Π°ΡΡΠ΅Π²ΠΎΠ³ΠΎ ΡΡΠ΅ΠΊΠ»Π° Ρ ΡΠΈΡΠΈΠ½ΠΎΠΉ ΠΎΡΠ½ΠΎΠ²Π°Π½ΠΈΡ 60 ΠΌΠΊΠΌ ΠΈ Π²ΡΡΠΎΡΠΎΠΉ 28,5 ΠΌΠΊΠΌ, ΠΎΡΠ²Π΅ΡΠ°Π΅ΠΌΠ°Ρ ΡΠ²Π΅ΡΠΎΠΌ Ρ Π΄Π»ΠΈΠ½ΠΎΠΉ Π²ΠΎΠ»Π½Ρ 4 ΠΌΠΊΠΌ, ΡΠΎΡΠΌΠΈΡΡΠ΅Ρ ΡΠΎΡΠΎΠ½Π½ΡΡ Π½Π°Π½ΠΎΡΡΡΡΡ Ρ ΠΌΠ°ΠΊΡΠΈΠΌΠ°Π»ΡΠ½ΠΎΠΉ ΠΈΠ½ΡΠ΅Π½ΡΠΈΠ²Π½ΠΎΡΡΡΡ, Π² 6 ΡΠ°Π· ΠΏΡΠ΅Π²ΡΡΠ°ΡΡΠ΅ΠΉ ΠΈΠ½ΡΠ΅Π½ΡΠΈΠ²Π½ΠΎΡΡΡ ΠΏΠ°Π΄Π°ΡΡΠ΅Π³ΠΎ ΠΈΠ·Π»ΡΡΠ΅Π½ΠΈΡ, ΠΈ ΡΠΈΡΠΈΠ½ΠΎΠΉ ΠΏΠΎ ΠΏΠΎΠ»ΡΡΠΏΠ°Π΄Ρ ΠΈΠ½ΡΠ΅Π½ΡΠΈΠ²Π½ΠΎΡΡΠΈ, ΡΠ°Π²Π½ΠΎΠΉ 0,38 ΠΎΡ Π΄Π»ΠΈΠ½Ρ Π²ΠΎΠ»Π½Ρ ΡΠΎΠΊΡΡΠΈΡΡΠ΅ΠΌΠΎΠ³ΠΎ ΠΈΠ·Π»ΡΡΠ΅Π½ΠΈΡ. Π Π°Π·ΠΌΠ΅ΡΡ ΡΠΎΠΊΡΡΠ½ΠΎΠ³ΠΎ ΠΏΡΡΠ½Π° ΠΌΠΎΠΆΠ½ΠΎ ΡΠΌΠ΅Π½ΡΡΠ°ΡΡ, Π΅ΡΠ»ΠΈ Π²ΡΡΠΎΡΠ° ΠΏΡΠΈΠ·ΠΌΡ ΠΏΠΎΠ΄ΠΎΠ±ΡΠ°Π½Π° ΡΠ°ΠΊΠΈΠΌ ΠΎΠ±ΡΠ°Π·ΠΎΠΌ, ΡΡΠΎΠ±Ρ ΠΌΠ°ΠΊΡΠΈΠΌΡΠΌ ΠΈΠ½ΡΠ΅Π½ΡΠΈΠ²Π½ΠΎΡΡΠΈ ΡΠ°ΡΠΏΠΎΠ»Π°Π³Π°Π»ΡΡ Π²Π½ΡΡΡΠΈ ΠΏΡΠΈΠ·ΠΌΡ. Π ΡΠ°ΡΡΠ½ΠΎΡΡΠΈ, ΠΏΡΠΈΠ·ΠΌΠ° ΠΈΠ· ΡΠΈΡΠ°Π½Π°ΡΠ° Π±Π°ΡΠΈΡ Ρ Π²ΡΡΠΎΡΠΎΠΉ 21 ΠΌΠΊΠΌ ΠΈ ΡΠΈΡΠΈΠ½ΠΎΠΉ ΠΎΡΠ½ΠΎΠ²Π°Π½ΠΈΡ 60 ΠΌΠΊΠΌ ΡΠΎΡΠΌΠΈΡΡΠ΅Ρ Π½Π΅ΠΏΠΎΡΡΠ΅Π΄ΡΡΠ²Π΅Π½Π½ΠΎ Π·Π° ΡΠ²ΠΎΠ΅ΠΉ Π²Π΅ΡΡΠΈΠ½ΠΎΠΉ ΡΠΎΠΊΡΡΠ½ΠΎΠ΅ ΠΏΡΡΠ½ΠΎ Ρ ΡΠΈΡΠΈΠ½ΠΎΠΉ, ΠΏΠΎ ΠΏΠΎΠ»ΡΡΠΏΠ°Π΄Ρ ΠΈΠ½ΡΠ΅Π½ΡΠΈΠ²Π½ΠΎΡΡΠΈ ΡΠ°Π²Π½ΠΎΠΉ 0,25 ΠΎΡ Π΄Π»ΠΈΠ½Ρ Π²ΠΎΠ»Π½Ρ ΡΠΎΠΊΡΡΠΈΡΡΠ΅ΠΌΠΎΠ³ΠΎ ΠΈΠ·Π»ΡΡΠ΅Π½ΠΈΡ.
ΠΡΠ»ΠΎ ΠΏΠΎΠΊΠ°Π·Π°Π½ΠΎ, ΡΡΠΎ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΠ΅ ΠΏΡΠΈΠ·ΠΌΡ ΠΏΡΠΈΠ²ΠΎΠ΄ΠΈΡ ΠΊ ΠΌΠ΅Π½ΡΡΠ΅ΠΉ Π·Π°Π²ΠΈΡΠΈΠΌΠΎΡΡΠΈ ΡΠΈΡΠΈΠ½Ρ ΡΠΎΠΊΡΡΠ½ΠΎΠ³ΠΎ ΠΏΡΡΠ½Π° ΠΎΡ Π΄Π»ΠΈΠ½Ρ Π²ΠΎΠ»Π½Ρ ΠΏΠΎ ΡΡΠ°Π²Π½Π΅Π½ΠΈΡ Ρ ΠΌΠΈΠΊΡΠΎΡΠΈΠ»ΠΈΠ½Π΄ΡΠΎΠΌ. ΠΠ°ΠΏΡΠΈΠΌΠ΅Ρ, Ρ ΠΌΠΈΠΊΡΠΎΡΠΈΠ»ΠΈΠ½Π΄ΡΠ° ΠΈΠ· ΠΊΠ²Π°ΡΡΠ΅Π²ΠΎΠ³ΠΎ ΡΡΠ΅ΠΊΠ»Π° Ρ Π΄ΠΈΠ°ΠΌΠ΅ΡΡΠΎΠΌ 60 ΠΌΠΊΠΌ ΡΠΌΠ΅Π½Π° Π΄Π»ΠΈΠ½Ρ Π²ΠΎΠ»Π½Ρ Ρ 3 ΠΌΠΊΠΌ Π΄ΠΎ 5 ΠΌΠΊΠΌ ΠΏΡΠΈΠ²ΠΎΠ΄ΠΈΡ ΠΊ ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΡ ΡΠΈΡΠΈΠ½Ρ ΠΏΡΡΠ½Π° Π½Π° 0,09 ΠΎΡ Π΄Π»ΠΈΠ½Ρ Π²ΠΎΠ»Π½Ρ ΡΠΎΠΊΡΡΠΈΡΡΠ΅ΠΌΠΎΠ³ΠΎ ΠΈΠ·Π»ΡΡΠ΅Π½ΠΈΡ, Π° Ρ ΠΏΡΠΈΠ·ΠΌΡ Π² ΡΡΠ΅Π΄Π½Π΅ΠΌ Π½Π° 0,05 ΠΎΡ Π΄Π»ΠΈΠ½Ρ Π²ΠΎΠ»Π½Ρ ΡΠΎΠΊΡΡΠΈΡΡΠ΅ΠΌΠΎΠ³ΠΎ ΠΈΠ·Π»ΡΡΠ΅Π½ΠΈΡ.
Using the finite difference method implemented in the COMSOL Multiphysics software package, the focusing of laser radiation by dielectric prisms with a triangular profile was numerically investigated. It was shown that two-dimensional triangular prisms make it possible to focus light in free space into spots with dimensions smaller than the scalar diffraction limit. In particular, a silica glass prism with a base width of 60 ΞΌm and a height of 28.5 ΞΌm forms a photonic nanojet with a maximum intensity of 6 times the intensity of the incident radiation and a width of FWHM=0.38Ξ». A prism from barium titanate with a base width of 60 ΞΌm and a height of 20 ΞΌm allows to obtain a photonic nanojet with the same width (0.38Ξ») and a maximum intensity 5 times the intensity of the incident radiation. The size of the focal spot can be reduced further if the height of the prism is selected so that the maximum intensity is located inside the material of the prism. For example, a barium titanate prism with a height of 21 ΞΌm and a base width of 60 ΞΌm forms a focal spot with a width of FWHM=0.25Ξ».Π Π°Π±ΠΎΡΠ° Π²ΡΠΏΠΎΠ»Π½Π΅Π½Π° ΠΏΡΠΈ ΠΏΠΎΠ΄Π΄Π΅ΡΠΆΠΊΠ΅ Π ΠΎΡΡΠΈΠΉΡΠΊΠΎΠ³ΠΎ Π€ΠΎΠ½Π΄Π° Π€ΡΠ½Π΄Π°ΠΌΠ΅Π½ΡΠ°Π»ΡΠ½ΡΡ
ΠΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΠΉ β Π³ΡΠ°Π½Ρ 18-07-01122 Π² ΡΠ°ΡΡΠΈ Β«Π€ΠΎΠΊΡΡΠΈΡΠΎΠ²ΠΊΠ° ΠΈΠ·Π»ΡΡΠ΅Π½ΠΈΡ ΡΡΠ΅ΡΠ³ΠΎΠ»ΡΠ½ΠΎΠΉ ΠΏΡΠΈΠ·ΠΌΠΎΠΉ ΠΈΠ· ΠΊΠ²Π°ΡΡΠ΅Π²ΠΎΠ³ΠΎ ΡΡΠ΅ΠΊΠ»Π°Β», Π³ΡΠ°Π½Ρ 18-07-01380 Π² ΡΠ°ΡΡΠΈ Β«Π€ΠΎΠΊΡΡΠΈΡΠΎΠ²ΠΊΠ° ΠΈΠ·Π»ΡΡΠ΅Π½ΠΈΡ ΠΊΡΡΠ³Π»ΡΠΌ ΡΠΈΠ»ΠΈΠ½Π΄ΡΠΎΠΌΒ» ΠΈ Π³ΡΠ°Π½Ρ 18-29-20003 Π² ΡΠ°ΡΡΠΈ Β«ΠΠ»ΠΈΡΠ½ΠΈΠ΅ ΠΏΠΎΠΊΠ°Π·Π°ΡΠ΅Π»Ρ ΠΏΡΠ΅Π»ΠΎΠΌΠ»Π΅Π½ΠΈΡ Π½Π° ΠΏΠ°ΡΠ°ΠΌΠ΅ΡΡΡ ΡΠΎΠΊΡΡΠ½ΠΎΠ³ΠΎ ΠΏΡΡΠ½Π°Β», ΠΈ ΠΠΈΠ½ΠΈΡΡΠ΅ΡΡΡΠ²Π° Π½Π°ΡΠΊΠΈ ΠΈ Π²ΡΡΡΠ΅Π³ΠΎ ΠΎΠ±ΡΠ°Π·ΠΎΠ²Π°Π½ΠΈΡ Π Π€ Π² ΡΠ°ΠΌΠΊΠ°Ρ
Π²ΡΠΏΠΎΠ»Π½Π΅Π½ΠΈΡ ΡΠ°Π±ΠΎΡ ΠΏΠΎ ΠΠΎΡΡΠ΄Π°ΡΡΡΠ²Π΅Π½Π½ΠΎΠΌΡ Π·Π°Π΄Π°Π½ΠΈΡ Π€ΠΠΠ¦ Β«ΠΡΠΈΡΡΠ°Π»Π»ΠΎΠ³ΡΠ°ΡΠΈΡ ΠΈ ΡΠΎΡΠΎΠ½ΠΈΠΊΠ°Β» Π ΠΠ Π² ΡΠ°ΡΡΠΈ Β«ΠΠ²Π΅Π΄Π΅Π½ΠΈΠ΅Β»
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