Bessel beam

About: Bessel beam is a research topic. Over the lifetime, 1946 publications have been published within this topic receiving 42264 citations.

Generation of Electron Bessel Beams with Nondiffractive Spreading by a Nanofabricated Annular Slit

Abstract: The shaping of a wavefront of free electrons has been experimentally realized very recently. We report the generation of an electron Bessel beam using a nanofabricated annular slit. We directly observe that electron Bessel beams propagate while maintaining a narrow beam width over a long propagation distance. In addition, we experimentally verify the self-healing property of these electron beams, which can reconstruct their shape after passing an obstacle. The experimental results are compared with simulation results of the propagation including a hexagonal slit. The present technique of electron Bessel beam generation can be used to develop a novel electron-beam-shaping, an atomic manipulation technique, and a new electron microscopy.

Side lobe suppression of a Bessel beam for high aspect ratio laser processing

Abstract: Bessel beams can be used for high aspect ratio laser drilling and for eliminating the need to precisely position materials along the propagation direction during laser drilling and cutting. However, Bessel beams have side lobes that can damage the materials subjected to these beams. This paper discusses optical suppression of side lobes. A method is proposed to suppress these side lobes, and the method is based on interference between two Bessel beams with different wave vectors. The effectiveness of this method is confirmed both theoretically and experimentally by realizing a superposed Bessel beam; using a He–Ne laser ( λ = 633 nm) and an annular binary aperture placed in front of a convex lens, this beam has a 1/ e 2 radius of 44 μm.

Generalization and propagation of spiraling Bessel beams with a helical axicon

Abstract: A generalized type of spiral Bessel beam has been demonstrated by using a spatially displaced helical axicon (HA). The topological charge of the spiraling Bessel beams is determined by the order of the input Laguerre—Gaussian (LG) beam and the topological charge of the HA. The obtained spiraling Bessel beams have an LG type of modulation along their propagation direction and exhibit annihilation-reconstruction properties. Theoretical analysis is presented, including that of the stability, propagation distance, topological charge, and spiraling dynamic characteristics. The mathematical and numerical results show that the propagation distance and helical revolution of the spiraling Bessel beams can be controlled through choosing appropriate radius of the HA.

Designing Appointed and Multiple Focuses With Plasmonic Vortex Lenses

Abstract: A plasmonic vortex lens (PVL), which enables to focus the spin or orbital angular momentum to a specific spatial position in the form of a plasmonic vortex, has been widely studied Here, we present a specific PVL structure to focus the surface plasmon polariton wave on an arbitrary spatial position Both analytical and numerical analyses are presented The plasmonic field of our PVL is an approximate Bessel beam In particular, the PVL can focus the input beam into a zeroth-order Bessel beam with a central peak Based on this principle, multiple focuses by combining multiple different PVLs are designed We can freely control the focuses just by changing the input modes Owing to the tuning ability of the focuses, these findings can motivate the applications for optical trapping, optical data, and digital display on chip

Microfabricated-composite-hologram-enabled multiple channel longitudinal optical guiding of microparticles in nondiffracting core of a Bessel beam array

Abstract: In this letter, we report multiple-channel longitudinal optical guiding of microparticles using an array of Bessel beams generated from a composite hologram fabricated by ultraviolet lithography. The optical guiding efficiency of each Bessel beam in the optical array is investigated experimentally. The rod-like core of each Bessel beam, with its nondiffracting and self-reconstruction property, has been shown to offer strong capability for optical guiding along the propagation axis possibly even in multiple-microfluidic channels massively.