Results 271 to 280 of about 1,200,672 (302)
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Numerical Treatment of Polar Coordinate Singularities
Journal of Computational Physics, 2000The authors present a method for eliminating the coordinate singularities whereby singular coordinates are redefined so that data are smoothly differentiated through the pole. The method avoids to place a grid point directly at the pole, and consequently eliminates the need for any pole equation.
Mohseni, Kamran, Colonius, Tim
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Polarization singularities in optical lattices
Optics Letters, 2004Polarization singularities are shown to be unavoidable features of three-dimensional optical lattices. These singularities take the form of lines of circular polarization, C lines, and lines of linear polarization, L lines. The polarization figures surrounding a C line (L line) rotate about the line with winding number +/-1/2 (+/-1).
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Measuring phase and polarization singularities of light using spin-multiplexing metasurfaces.
Nanoscale, 2019In recent years, light beams containing phase or polarization singularities, such as optical vortices (OVs) and cylindrical vector beams (CVBs), have contributed to significant applications including optical orbital angular momentum (OAM) communications,
Yanan Fu +11 more
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Observing vortex polarization singularities at optical band degeneracies
Physical review B, 2019Ang Chen,1,3 Wenzhe Liu,1,3 Yiwen Zhang,1,3 Bo Wang,1,3 Xiaohan Liu,1,3 Lei Shi,1,3,* Ling Lu,2 and Jian Zi1,3,† 1Department of Physics, Key Laboratory of Microand Nano-Photonic Structures (Ministry of Education), and State Key Laboratory of Surface ...
Ang Chen +7 more
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Hexagonal vector field of polarization singularities with a gradient basis structure.
Optics Letters, 2019The coherent superposition of vector fields can yield interesting field distributions. For example, the superposition of two right-handed polarization singularities can result in left-handed polarization singularities.
S. Pal, P. Senthilkumaran
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Gaussian beams with multiple polarization singularities
Optics Communications, 2018In recent years, alongside light beams with phase singularities (so-called optical vortices), polarization vortices (including beams with radial and azimuthal polarization) have also been studied.
A. Kovalev, V. Kotlyar
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Second-harmonic generation of polarization singularities
Optics Letters, 2002Second-harmonic generation was studied theoretically for the vector singularities (daisy modes) of linearly polarized light and for the elliptic singularities (C points) of elliptically polarized light. Topological charge doubling for C points and daisy modes, similar to that found for vortices, was found.
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Tailoring polarization singularities in a Gaussian beam with locally linear polarization.
Optics Letters, 2018Here we theoretically study Gaussian beams with arbitrarily located polarization singularities (PSs). Under PSs, we mean here an isolated intensity null with radial, azimuthal, or radial-azimuthal polarization around it. An expression is obtained for the
A. Kovalev, V. Kotlyar
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ON CONTINUATION OF FUNCTIONS WITH POLAR SINGULARITIES
Mathematics of the USSR-Sbornik, 1988See the review in Zbl 0617.32018.
Sadullaev, A., Chirka, E. M.
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Optical polarization singularities and elliptic stationary points
Optics Letters, 2003Polarization singularities and elliptic stationary points (collectively, elliptic critical points) were measured experimentally via the complex Stokes field S1 + iS2, where S1 and S2 are Stokes parameters. This new, easily implemented method yielded detailed, high-resolution experimental data for all elliptic critical points.
Marat S, Soskin +2 more
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