Results 1 to 10 of about 23,183 (245)
High numerical aperture metalens to generate an energy backflow [PDF]
Компьютерная оптика, 2020 Using electronic beam lithography and reactive ion beam etching, a metalens is manufactured in a thin layer of amorphous silicon of a 130-nm depth, a 30-µm diameter, and a 633-nm focal length (equal to the illumination wavelength).
V.V. Kotlyar +3 more
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Energy Characteristics of Full Tubular Pump Device with Different Backflow Clearances Based on Entropy Production [PDF]
Applied Sciences, 2021 In this study, the entropy theory was used as the evaluation standard of energy dissipation, and the effect of backflow clearance (the gap between motor rotor and motor shell) on energy characteristics of a full tubular pump was investigated by 3D ...
Fan Meng, Yanjun Li, Ji Pei
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"Plasmonics" in free space: observation of giant wavevectors, vortices, and energy backflow in superoscillatory optical fields. [PDF]
Light Sci Appl, 2019 AbstractEvanescent light can be localized at the nanoscale by resonant absorption in a plasmonic nanoparticle or taper or by transmission through a nanohole. However, a conventional lens cannot focus free-space light beyond half of the wavelength λ. Nevertheless, precisely tailored interference of multiple waves can form a hotspot in free space of an ...
Yuan G, Rogers ETF, Zheludev NI.
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Formation of an elongated region of energy backflow using ring apertures [PDF]
Компьютерная оптика, 2019 In this paper, we have investigated the focusing of a second-order cylindrical vector beam by using a high numerical aperture (NA) lens limited by a ring aperture using the Richards-Wolf formulae.
Sergey Stafeev, Victor Kotlyar
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Experimental investigation of the energy backflow in the tight focal spot [PDF]
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
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The near-axis backflow of energy in a tightly focused optical vortex with circular polarization [PDF]
Компьютерная оптика, 2018 Using the Richards-Wolf formulae for a diffractive lens, we show that in the focal plane of a sharply focused left-hand circularly polarized optical vortex with the topological charge 2 there is an on-axis backflow of energy (as testified by the negative
Victor Kotlyar +2 more
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Energies, 2022 A novel method characterizing the air backflow of the underhood in order to improve the thermal efficiency of the air conditioning system (ACS) and reduce the energy consumption of PHEV is proposed in this paper. In addition, a 1D model for analyzing air
Haibo Wu +3 more
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Energy backflow in a focal spot of the cylindrical vector beam [PDF]
Компьютерная оптика, 2018 Using Richards-Wolf formulae it is shown that a tightly focused azimuthally-radially polarized m-th order laser beam with an arbitrary apodization function produces a reverse energy flow in the focal plane (m=2).
Sergey Stafeev +2 more
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Energy Backflow in Unidirectional Monochromatic and Space–Time Waves
PhotonicsBackflow, or retropropagation, is a counterintuitive phenomenon whereby for a forward-propagating wave the energy locally propagates backward. In the context of backflow, physically most interesting are the so-called unidirectional waves, which contain ...
Peeter Saari, Ioannis M. Besieris
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Photonics, 2023 Using the Richards–Wolf diffraction integral, the longitudinal energy evolution on the focal plane of the fractional order vector vortex (FOVV) beams was studied. These beams possessed a vortex topological charge n and a polarization topological charge m,
Yan Wu, Xiaobo Hu, Yuhua Li, Ruipin Chen
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