Bessel beam

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

Orbital angular momentum of a high order Bessel light beam

Abstract: Summary form only given. We demonstrate experimentally for the first time, that a high order Bessel beam possesses orbital angular momentum (OAM). We demonstrate transfer of OAM from such a beam to trapped transparent particles in optical tweezers. Additionally, we examine theoretically, within a rigorous vectorial treatment, the local angular momentum density for a high order Bessel beam (HOBB) and find local variations in this density when compared to Laguerre-Gaussian beams. For transparent particles the orbital angular momentum is transferred by scattering/reflection of the incident light beam as in the case of metallic particles. Importantly we obtained quantitative results for the rotation rate which has a linear dependence on the orbital angular momentum content of the light beam. The measured rotation rates correspond to a transfer of about 1% of the Bessel beam's orbital angular momentum which is consistent with calculations based on a transfer mechanism due to scattering.

Bessel Beam: Significance and Applications-A Progressive Review.

Abstract: Diffraction is a phenomenon related to the wave nature of light and arises when a propagating wave comes across an obstacle. Consequently, the wave can be transformed in amplitude or phase and diffraction occurs. Those parts of the wavefront avoiding an obstacle form a diffraction pattern after interfering with each other. In this review paper, we have discussed the topic of non-diffractive beams, explicitly Bessel beams. Such beams provide some resistance to diffraction and hence are hypothetically a phenomenal alternate to Gaussian beams in several circumstances. Several outstanding applications are coined to Bessel beams and have been employed in commercial applications. We have discussed several hot applications based on these magnificent beams such as optical trapping, material processing, free-space long-distance self-healing beams, optical coherence tomography, superresolution, sharp focusing, polarization transformation, increased depth of focus, birefringence detection based on astigmatic transformed BB and encryption in optical communication. According to our knowledge, each topic presented in this review is justifiably explained.

Large Depth of Field Pseudo-Bessel Beam Generation With a RLSA Antenna

Abstract: The paper discusses the possibility of generating a pseudo-Bessel beam, with a propagation distance of several hundreds of wavelengths in microwave and millimeter frequency band, by using a radial line slot array (RLSA). A specific application for non-contact microwave detection of buried mines has been considered as test case. The design benefits of a holographic approach to assure the required aperture field distribution and makes use of an ad hoc optimization tool to control the antenna slot layout. The predicted and measured antenna behaviors show that high efficiency and polarization purity can be obtained by such a compact and flat antenna, achieving at the same time both manufacturing and setup simplicity.

Rotation of microparticles with Bessel beams generated by diffractive elements

Abstract: We show that imaging a non-diverging Bessel beam by a spherical lens leads to the generation of a diverging Bessel beam. Expressions for the projections of the Umov-Poynting vector for a two-dimensional TE-polarized Bessel beam and a three-dimensional paraxial linearly polarized Bessel beam are derived. A fifth-order Bessel beam is produced using a single optical element-a 16-level phase-only diffractive helical axicon fabricated using electron beam lithography. This beam was successfully used to trap and rotate 5-10 μm diameter yeast particles and polystyrene beads of diameter 5 μm.