Collinear acousto-optical filtration of polychromatic Bessel light beams in lithium niobate crystals

The features of collinear acousto - optical filtration of quasi - diffractive Bessel light beams of o- and e-type in uniaxial crystals are investigated. Using the method of overlap integrals, an expression is found for the diffraction efficiency depending on the parameters of the acousto-optical interaction, as well as on the values of the overlap integrals. It is shown that for the zero-order mode of a Bessel light beam for a lithium niobate crystal under conditions of transverse phase synchronism and in the optical spectrum range of 0.4-0.7 μm, the filter bandwidth of ∼0.2 nm is achievable; with an increase in the order of the mode m≥1, the increase in the bandwidth is insignificant and is ∼0.23 -0.24 nm.

Some features of acousto-optic interaction of optical and acoustic Bessel beams in transversely isotropic optically positive crystals

Some basic properties of acousto-optical (AO) diffraction involving Bessel light and acoustic beams in anisotropic crystals are investigated. Hexagonal symmetry crystals are considered and are optically uniaxial and positive and acoustically transversely isotropic. It is shown that, unlike the case of AO diffraction of plane waves, the transition to Bessel beams allows one to realize a number of new diffraction channels having specific configurations of the wave vectors of interacting waves while maintaining the axial symmetry of the optical scheme as a whole. The diffraction channels for anisotropic scattering are classified and the main parameters of the scattered Bessel light beam and the parameters of the Bessel acoustic beam are calculated for each of them. The possibility of implementing the isotropic-type diffraction was revealed, which makes it possible to increase the efficiency of AO conversion. The parameters of this-type diffraction are determined for two scattering channels, namely, for scattering by a direct Bessel acoustic beam and by a backward propagating acoustic beam.Due to the appearance of a set of scattering channels and with regard to the fact that Bessel light and acoustic beams have helical wave front dislocations, as well as suppressed diffraction spreading, the study of the features of AO diffraction of such beams in optically positive crystals has both a scientific and practical interest.

Transformation of Evanescent Bessel Light Beams into Propagating Quasi-Nondiffracting Beams in Epsilon-Near-Zero Hyperbolic Metamaterials

In this paper, we show the possibility of rebuilding of the structure of wave vector surface and the appearance of its local parts with near zero curvature for epsilon-near-zero hyperbolic metamaterials. It is established that when evanescent Bessel light beam falls in special directions related to these local parts, it is transformed into propagating one. The features of transformed beam are analyzed.

Manipulation of Microparticles By Bessel Light Beam

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Axial Angular Momentum of Bessel Light

Both linear and angular momentum densities of Bessel, Gaussian-Bessel, and Hankel-Bessel lasers are determined. Angular momentum of the three Bessel beams is illustrated at linear and circular polarization. Axial Angular momentum is resolved in particular interpretation: the harmonic order of the physical light momentum. Full Text: PDF ReferencesG. Molina-Terriza, J. Torres, and L. Torner, "Twisted photons", Nature Physics 3, 305 - 310 (2007). CrossRef J Arlt, V Garces-Chavez, W Sibbett, and K Dholakia "Optical micromanipulation using a Bessel light beam", Opt. Commun., 197, 4-6, (2001). CrossRef L. Ambrosio and H. Hernández-Figueroa, "Gradient forces on double-negative particles in optical tweezers using Bessel beams in the ray optics regime", Opt Exp, 18, 23 (2010). CrossRef I. Litvin, A. Dudley and A. Forbes, "Poynting vector and orbital angular momentum density of superpositions of Bessel beams", Opt Exp, 19, 18 (2011). CrossRef K Volke-Sepulveda, V Garcés-Chávez, S Chávez-Cerda, J Arlt and K Dholakia "Orbital angular momentum of a high-order Bessel light beam" , JOP B 4 (2). 2002. CrossRef M. Verma, S. Pal, S. Joshi, P. Senthilkumaran, J. Joseph, and H Kandpal, "Singularities in cylindrical vector beams", Jou. of Mod. Opt., 62 (13), 2015. CrossRef R. Borghi, M. Santarsiero, and M. Porras, "Nonparaxial Bessel?Gauss beams", J. Opt. Soc. Am. A, 18 (7) (2011). CrossRef L. Allen, M. Beijersbergen, R. Spreeuw, and J. Woerdman, "Orbital angular momentum of light and the transformation of Laguerre-Gaussian Laser modes", Phys Rev A, 45 (11): 8185-8189 (1992). CrossRef D. Mcglion and K. Dholakia, "Bessel beams: diffraction in a new light", Cont. Phys, 46(1) 15 ? 28. (2005). CrossRef F. Gori, G. Guattari and C. Padovani," Bessel-Gauss Beams", Opt. Commun., 64, 491, (1987). CrossRef V. Kotlyar, A. Kovalev, and A. Soifer, "Hankel?Bessel laser beams" J. Opt. Soc. Am. A, 29 (5) (2012). CrossRef L. Allen and M. Babiker "Spin-orbit coupling in free-space Laguerre-Gaussian light beams", Phys. Rev. A 53, R2937. CrossRef