Results 21 to 30 of about 443,393 (289)
Photonics, 2022 In this paper, using the Richards–Wolf equations, the focusing of circularly polarized light with flat diffractive lenses is considered. It is shown that, as the numerical aperture (NA) of the lens increases, the size of the focal spot first decreases ...
Sergey S. Stafeev +2 more
doaj +1 more source
Experimental investigation of the energy backflow in the tight focal spot
Компьютерная оптика, 2020 Using two identical microobjectives with a numerical aperture NA = 0.95, we experimentally demonstrate that the on-axis intensity near the tight focal spot of an optical vortex with a topological charge 2 is zero for right-handed circular polarization ...
V.V. Kotlyar +4 more
doaj +1 more source
Vector Beams with Only Transverse Intensity at Focus
Applied Sciences, 2023 In this work, the tight focusing of vector beams with azimuthal polarization and beams with a V-line of polarization singularity (sector azimuthal polarization) was simulated numerically using the Richards–Wolf formulas.
Sergey S. Stafeev +4 more
doaj +1 more source
Boron and nitrogen doping in graphene antidot lattices [PDF]
, 2016 Bottom-up fabrication of graphene antidot lattices (GALs) has previously yielded atomically precise structures with sub-nanometer periodicity. Focusing on this type of experimentally realized GAL, we perform density functional theory calculations on the ...
Brun, Søren J. +2 more
core +3 more sources
Band-specific phase engineering for curving and focusing light in waveguide arrays [PDF]
, 2012 Band specific design of curved light caustics and focusing in optical waveguide arrays is introduced. Going beyond the discrete, tight-binding model, which we examined recently, we show how the exact band structure and the associated diffraction ...
Chremmos, Ioannis +1 more
core +1 more source
Minimal focal spot obtained by focusing circularly polarized light
Компьютерная оптика, 2023 In this paper, using the Richards-Wolf equations, we analyze focusing circularly polarized light with flat diffractive lenses. It is shown that as the numerical aperture of the lens increases, the size of the focal spot first decreases and then begins to
S.S. Stafeev, V.D. Zaitcev, V.V. Kotlyar
doaj +1 more source
Realistic laser focusing effect on electron acceleration in the presence of a pulsed magnetic field [PDF]
, 2014 As we know, for a significant electron energy gain, a fast electron should be injected into the highest intensity region of the laser focus. Such intensities may be achieved in the laboratory by tight focusing of a laser.
Gupta, Devki Nandan +2 more
core +1 more source
Optimized Computation of Tight Focusing of Short Pulses Using Mapping to Periodic Space
Applied Sciences, 2021 When a pulsed, few-cycle electromagnetic wave is focused by optics with f-number smaller than two, the frequency components it contains are focused to different regions of space, building up a complex electromagnetic field structure.
Elena Panova +11 more
doaj +1 more source
The Non-Vortex Inverse Propagation of Energy in a Tightly Focused High-Order Cylindrical Vector Beam
IEEE Photonics Journal, 2019 In this paper, the tight focusing of high-order cylindrical vector beams (beams with polarization singularity) was investigated. Using the Richards–Wolf formalism, there were obtained expressions for all projections of the electric and magnetic ...
Sergey S. Stafeev +3 more
doaj +1 more source
Multi-twist polarization ribbon topologies in highly-confined optical fields
New Journal of Physics, 2019 Electromagnetic plane waves, solutions to Maxwell’s equations, are said to be ‘transverse’ in vacuum. Namely, the waves’ oscillatory electric and magnetic fields are confined within a plane transverse to the waves’ propagation direction.
Thomas Bauer +8 more
doaj +1 more source