Results 11 to 20 of about 67,616 (299)
Inverse Energy Flux in Tight Focusing of Vector Vortex Beam
Photonics, 2023 In this paper, we focus on the study of the negative energy flow in the tight focusing of a radially polarized vortex beam. We know that, because of the coupling of the polarization state and the vortex charge, the on-axis energy flow in the focal region
Ruixiang Chen +4 more
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Propagation equation for tight-focusing by a parabolic mirror
Optics Express, 2015 Part of the chain in petawatt laser systems may involve extreme focusing conditions for which nonparaxial and vectorial effects have high impact on the propagation of radiation. We investigate the possibility of using propagation equations to simulate numerically the focal spot under these conditions. We derive a unidirectional propagation equation for
Couairon, Arnaud +6 more
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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
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Absorption-limited and phase-matched high harmonic generation in the tight focusing regime [PDF]
New Journal of Physics, 2014 High harmonic generation (HHG) at a high repetition rate requires tight focusing of the moderate peak power driving pulses. So far the conversion efficiencies that have been achieved in this regime are orders of magnitude behind the values that have been
Jan Rothhardt +5 more
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Modeling the tight focusing of beams in absorbing media with Monte Carlo simulations
Journal of Biomedical Optics, 2014 A severe drawback to the scalar Monte Carlo (MC) method is the difficulty of introducing diffraction when simulating light propagation. This hinders, for instance, the accurate modeling of beams focused through microscope objectives, where the diffraction patterns in the focal plane are of great importance in various applications.
Arnd Brandes +3 more
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Photonics, 2023 A thorough integral formulation describing the second harmonic generation under tightly focused linearly and radially polarized beams for an arbitrary distribution of the nonlinear susceptibility over the surface of isotropic media was presented.
Sergey Scherbak +3 more
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A minimal subwavelength focal spot for the energy flux
Компьютерная оптика, 2021 It is shown theoretically and numerically that circularly and linearly polarized incident beams produce at the tight focus identical circularly symmetric distributions of an on-axis energy flux.
S.S. Stafeev, V.D. Zaicev
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Comparison of focusing of short pulses in the Debye approximation [PDF]
Компьютерная оптика, 2018 We have examined different types of pulses and features of their frequency spectra. Calculations have shown that a significant distinction between the pulses only takes place at a very short pulse duration (shorter than the oscillation period).
Svetlana Khonina +2 more
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Tailoring of Inverse Energy Flow Profiles with Vector Lissajous Beams
Photonics, 2022 In recent years, structured laser beams for shaping inverse energy flow regions: regions with a direction of energy flow opposite to the propagation direction of a laser beam, have been actively studied.
Svetlana N. Khonina +4 more
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