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Quantum backflow, negative kinetic energy, and optical retro-propagation
Journal of Physics A: Mathematical and Theoretical, 2010 For wavefunctions whose fourier spectrum (wavenumber or frequency) is positive, the local phase gradient can sometimes be negative; examples of this 'backflow' occur in quantum mechanics and optics. The backflow probability P (fraction of the region that is backflowing) is calculated for several cases.
M V Berry
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Energy backflow in the focus of an optical vortex
Laser Physics, 2018By employing Richards-Wolf formulae for an aplanatic system, we show that when tightly focusing a left-hand circularly polarized optical vortex with the topological charge 2 and an arbitrary apodization function, an on-axis energy backflow occurs in the focus plane, which is verified by a negative optical-axis projection of the Poynting vector.
VÍCTOR V Kotlyar +2 more
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Elongation of the area of energy backflow through the use of ring apertures
Optics Communications, 2019Abstract Using the Richards–Wolf formula, we investigate the tight focusing of a cylindrical vector beam of second order using a high-numerical aperture lens confined by a ring aperture. It is shown that the area of energy backflow can be enlarged by the ring aperture, and that focusing light using a lens with a numerical aperture of 0.95 and a ring ...
Sergey S Stafeev, VÍCTOR V Kotlyar
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Optical Technologies for Telecommunications 2020, 2021
Using electronic beam lithography and ion etching we manufactured a metalens with diameter 30 μm, focal length 633 nm and relief depth of 130 nm. The metalens consists from 16 sector subwavelength binary gratings with period 220 nm. The proposed metalens generates a left-hand circularly polarized optical vortex with topological charge 2 when it is ...
Sergey S. Stafeev +4 more
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Using electronic beam lithography and ion etching we manufactured a metalens with diameter 30 μm, focal length 633 nm and relief depth of 130 nm. The metalens consists from 16 sector subwavelength binary gratings with period 220 nm. The proposed metalens generates a left-hand circularly polarized optical vortex with topological charge 2 when it is ...
Sergey S. Stafeev +4 more
openaire +1 more source
Journal of Optics, 2019
Abstract Using the plane waves expansion, we derive all six components of the E- and H-vectors for an elliptically polarized optical vortex with the arbitrary topological charge. Relations to describe the distributions of intensity and components of the Poynting vector in the initial plane of the optical vortex are also derived.
Victor V Kotlyar, Alexey A Kovalev
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Abstract Using the plane waves expansion, we derive all six components of the E- and H-vectors for an elliptically polarized optical vortex with the arbitrary topological charge. Relations to describe the distributions of intensity and components of the Poynting vector in the initial plane of the optical vortex are also derived.
Victor V Kotlyar, Alexey A Kovalev
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Energy Backflow in Tightly Focused Optical Vortex
2018 20th International Conference on Transparent Optical Networks (ICTON), 2018We numerically investigated the focusing of optical vortices with topological charge of 2, wavelength of 532 nm and circular polarization by a diffractive lens with a numerical aperture NA = 0.95. The simulation was carried out using the Richards-Wolf formulae and FDTD-method.
Sergey S. Stafeev +2 more
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Gigantic wavevectors and energy backflow in the focus of a super-oscillatory lens
2017 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC), 2017We provide the first explicit experimental evidence of gigantic values of wavevectors and energy backflow in the field structure of a super-oscillatory lens. These observations explain how such a lens can focus light into a spot beyond the diffraction limit.
G. H. Yuan, N. Zheludev
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Energy backflow in in a tightly focused high-order cylindrical vector beam
Metamaterials XII, 2019In this work, the tight focusing of high-order cylindrical vector beams was investigated. Our analysis relies upon the Richard-Wolf equations, which have been extensively utilized when studying tightly focused laser beams with due regard for the vector properties of light fields.
Sergey Stafeev +2 more
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