Analyzing the spectral characteristics of a pulsed Laguerre higher-order cosh-Gaussian beam propagating through a paraxial ABCD optical system

A dual-plane terahertz hologram based on diffractive optical elements is presented. A 2D dielectric array THz hologram with elements comprised of various heights is designed by applying a nonlinear optimization method. The designed hologram masks are fabricated using 3D printing technology. Full-wave FDTD simulations and experimental results demonstrate that the designed hologram can achieve dual-plane imaging, which has the potential to be used in displays and data storage.

Dual-plane Terahertz Hologram with Diffractive Optical Elements

Abstract In this paper, we generate a new doughnut Humbert beam from a Whittaker-Gaussian (WG) beam propagating through a gradient-index medium (GIM). Based on the extended Huygens-Fresnel diffraction integral, the analytical expression of the intensity distribution for doughnut Humbert beam is derived and discussed through numerical examples. The obtained results indicate that the diffracted beam evolves periodically versus the propagation distance in GIM and its behavior depends interestingly on the beam initial parameters and the gradient-index parameter. Our results can be useful for some applications such as in multi-dimensional optical manipulation, remote sensing domain and imaging. 

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Generation of doughnut Humbert beam by a gradient-index medium

Analysis of the behavior of pulsed vortex beams in oceanic turbulence

Spectral properties of pulsed Laguerre higher-order cosh-Gaussian beam propagating through the turbulent atmosphere


 In this paper, we discuss the quality of holograms based on the calculation of the modulation depth. It’s shown that the terahertz (THz) pulsed vortex beams play a vital role in holography filed, where two lasers with frequency difference have used. The THz vortex beams give new regions of larger frequency detuning and an important value of the modulation depth and fringe contrast (MDFC ratio) for obtaining the best holograms contrary to the Gaussian beams for which the best holograms are realized for small frequency detuning. The particular cases such as, Gaussian beam and single cycle pulses are deduced from our result. Numerical simulations are also presented to study the dependence of the MDFC ratio on the frequency detuning for THz vortex beams and Gaussian beams. This research could be beneficial in holographic interferometry, and it will firmly establish as a tool for scientific and engineering studies.

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Halima Benzehoua

Papers

Production of good quality holograms by the THz pulsed vortex beams

Analyzing the spectral characteristics of a pulsed Laguerre higher-order cosh-Gaussian beam propagating through a paraxial ABCD optical system

Effects of Hollow–Gaussian beams on Fresnel diffraction by an opaque disk

Analysis of the behavior of pulsed vortex beams in oceanic turbulence

An advanced method for evaluating Lommel integral and its application in marine environment