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1
Content available Review on the structured light properties : rotational features and singularities
Angelsky Oleg V., Bekshaev Aleksandr Ya., Mokhun Igor I., Vasnetsov Mikhail V., Zenkova Claudia Yu., Hanson Steen G., Zheng Jun
Opto-Electronics Review
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2022
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Vol. 30, No. 2
art. no. e140860
EN
The review exposes basic concepts and manifestations of the singular and structured light fields. The presentation is based on deep intrinsic relations between the singularities and the rotational phenomena in light; it involves essentially the dynamical aspects of light fields and their interactions with matter. Due to their topological nature, the singularities of each separate parameter (phase, polarization, energy flow, etc.) form coherent interrelated systems (singular networks), and the meaningful interconnections between the different singular networks are analysed. The main features of singular-light structures are introduced via generic examples of the optical vortex and circular vortex beams. The review describes approaches for generation and diagnostics of different singular networks and underlines the role of singularities in formation of optical field structures. The mechanical action of structured light fields on material objects is discussed on the base of the spin-orbital (canonical) decomposition of electromagnetic momentum, expressing the special roles of the spin (polarization) and spatial degrees of freedom. Experimental demonstrations spectacularly characterize the topological nature and the immanent rotational features of the light-field singularities. The review is based on the results obtained by its authors with a special attention to relevant works of other researchers.
2
Content available Abruptly autofocusing property of circular Pearcey vortex beams with different initial launch angles in harmonic potentials
Liu Xianglian, Zhang Di, Zhao Lijiao, Li Pu, Zhang Jianguo, Liu Yi
Optica Applicata
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2022
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Vol. 52, nr 3
417--428
EN
We have studied and explored the influence of different launch angles on the circular Pearcey beams (CPBs) without vortex or with vortex for the first time. Although launch angles can manipulate the focal length and the contrast of peak intensity of the CPBs, the shape and propagation trajectory of the CPBs maintain invariant. When the vortex is considered, the focal pattern and the contrast of peak intensity of the circular Pearcey vortex beams (CPVBs) can be changed by adjusting the magnitude of topological charges and the position of vortex. In addition, we have deliberated the propagation of the CPVBs under the action of double opposite optical vortices.
3
Localized optical vortex solitons in pair plasmas
Medina Luciano
Journal of Applied Analysis
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2021
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Vol. 27, nr 1
1--12
EN
The dynamics of short intense electromagnetic pulses propagating in a relativistic pair plasma is governed by a nonlinear Schrödinger equation with a new type of focusing-defocusing saturable nonlinearity. In this context, we provide an existence theory for ring-profiled optical vortex solitons. We prove the existence of both saddle point and minimum type solutions. Via a constrained minimization approach, we prove the existence of solutions where the photon number may be prescribed, and we get the nonexistence of small-photon-number solutions.We also use the constrained minimization to compute the soliton’s profile as a function of the photon number and other relevant parameters.
4
On the cubic and cubic-quintic optical vortices equations
Greco C.
Journal of Applied Analysis
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2016
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Vol. 22, nr 2
95--105
EN
An optical vortex can appear when a light beam with nonzero angular momentum propagates in a suitable nonlinear medium. In some situations has been observed that the light intensity vanish at the center of the vortex (where the phase of the electromagnetic field is undefined), while the light beam assumes a ring-shaped structure. In this paper we consider two classical cases in which such kind of phenomena occur: the case of the self focusing cubic nonlinearity, and the case of competing quintic and cubic nonlinearity. In both cases we study the nonlinear Schrödinger equation of the optical field (with various boundary conditions) by means of min-max methods, and we prove the existence of saddle point type solutions, as well as minimum type solutions.
5
Content available Extraordinary optical transmission and vortex excitation by periodic arrays of Fresnel zone plates
Roszkiewicz A., Nasalski W.
Bulletin of the Polish Academy of Sciences. Technical Sciences
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2013
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Vol. 61, nr 4
855--861
EN
Extraordinary optical transmission and good focusing properties of a two-dimensional scattering structure is presented. The structure is made of Fresnel zone plates periodically arranged along two orthogonal directions. Each plate consists of two ring-shaped waveguides supporting modes that match the symmetry of a circularly polarized incident plane wave. High field concentration at the focal plane is obtained with the short transverse and long longitudinal foci diameters. Optical vortex excitation in a paraxial region of the transmitted field is also observed and analysed in terms of cross-polarisation coupling. The structure presented may appear useful in visualization, trapping and precise manipulations of nanoparticles.
6
Content available remote Transmission of Elegant Laguerre-Gaussian beams at a dielectric interface - numerical simulations
Szabelak W., Nasalski W.
Bulletin of the Polish Academy of Sciences. Technical Sciences
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2009
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Vol. 57, nr 2
181-188
EN
Behavior of Laguerre-Gaussian beams impinged at a dielectric interface under distinct angles is discussed. For different incident angles the beams interact with the interface differently. Two ranges of incident angles, specified by a position of a spectral cone of beam field and related to a cross-polarization effect, are analyzed. Boundary between these two ranges is defined. Cases of critical incidence and total internal reflection are also discussed. Paraxial beams near the lower paraxial limit are considered. Theoretical predictions are confirmed by numerical simulations.
7
Content available remote Optical vortices as phase markers to wave-front deformation measurement
Frączek W., Mroczka J.
Metrology and Measurement Systems
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2008
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Vol. 15, nr 4
433-440
EN
In this paper a new method to the test deformation of the wave-front of the plane wave is presented. In the method Optical Vortex Interferometry is applied. In the OVI a regular lattice of optical vortices is generated by the interference of three plane waves. The wave-front of one wave is deformed after crossing the measured object. The deformation of the wave-front is measurable because the deformation of vortex lattice structure arises from the wave-front deformation. The record of the positions of the vortex points before and after the object insertion in the optical arrangement is essential. The analysis of the change of vortex points positions, as shown in this paper gives highly precise information about the real deformation of the wave-front caused by the object insertion.
8
Content available remote Influence of selected factors for localization accuracy in the Optical Vortex Interferometer
Frączek E., Mroczka J.
Metrology and Measurement Systems
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2008
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Vol. 15, nr 1
3-8
EN
Optical vortices were intensively studied during the last decade. In the literature there are papers presenting applications of the optical vortices. The regular net of optical vortices generated by the three plane waves interference allows for the new kind of the interferometer - the Optical Vortex Interferometer (OVI). The precision of the OVI depends on the localization accuracy and the phase reconstruction. The localization methods lead to errors if we use beamsplitters with coatings changing the polarization state of the light. There are six beamsplitters used in this interferometer. In the setup we used non-polarizing coatings. We observed a pleochroism effect which occurs in these coatings. It is the cause of errors in the localization of optical vortices. In this paper we study the effect of pleochroism and we show the way to avoid errors in the localization of optical vortices in the OVI.
9
Content available remote Stable spinning optical solitons in two and three dimensions
Mihalache D.
Opto-Electronics Review
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2005
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Vol. 13, No. 2
123-127
EN
A brief overview of recent results in the field of multidimensional spinning (vortex) optical solitons is given. We address the stability problem of two- and three-dimensional spinning solitons in media with competing nonlinearities. We conclude that these solitons could be stable, provided that their external size and power (energy) are large enough. The stability of vorticity-carrying solitons is a generic feature of media with competing self-focusing and self-defocusing nonlinearities.
10
Content available remote Creation and diagnostics of stable rainbow optical vortices
Arkhelyuk O. O., Polyanskii P. V., Ivanovskii A. A., Soskin M. S.
Optica Applicata
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2004
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Vol. 34, nr 3
419-426
EN
An on-axis computer-synthesized hologram-based technique is introduced to create white-light “rainbow” optical vortices, which are stable with respect to environmental disturbances under long-distance propagation of singularity supporting beams. Regularities governing the radial alternation of colors at highly directed rainbow vortices are discussed. The original diffraction technique for detecting phase singularities is applied to reveal and diagnose the polychromatic vortices
11
Content available remote Referenceless testing of vortex optical beams
Bogatiryova H. V., Felde C. V., Polyanskii P. V.
Optica Applicata
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2003
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Vol. 33, nr 4
695-708
EN
A new simple technique for determining the phase handedness (clockwise or counterclockwise) of vortex optical beams, which does not require implementation of an interferometric arrangement, is introduced. It is shown that both the phase handedness and the modulus of an azimuthal mode index of the beam can be directly and unambiguously determined on the basis of bending of interference fringes in a “strip” Young’s interference experiment. The initial results are obtained by simulation, partially demonstrated and discussed. Applicability of the proposed technique to testing elementary and complex vortex-bearing optical beams and fields is discussed
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