Peculiarities of focusing circularly and radially polarized super-Gaussian beams using ring gratings with varying relief height

The focusing features of a super-Gaussian beam, as well as Laguerre-super-Gaussian (1,0) modes with radial and circular polarizations on ring gratings (direct and inverse) with a variable height of individual relief rings were investigated in this paper. The change in the height of the relief from t...

Full description

Bibliographic Details
Main Author: D.A. Savelyev
Format: Article
Language:English
Published: Samara National Research University 2022-08-01
Series:Компьютерная оптика
Subjects:
Online Access:https://computeroptics.ru/eng/KO/Annot/KO46-4/460404e.html
_version_ 1797794529946894336
author D.A. Savelyev
author_facet D.A. Savelyev
author_sort D.A. Savelyev
collection DOAJ
description The focusing features of a super-Gaussian beam, as well as Laguerre-super-Gaussian (1,0) modes with radial and circular polarizations on ring gratings (direct and inverse) with a variable height of individual relief rings were investigated in this paper. The change in the height of the relief from the maximum height in the center to the minimum at the edges of the element (direct ring grating) is considered and the reverse case, when the maximum height of the relief was at the edges and the minimum in the center (reverse ring grating). The comparison was carried out with the action of a diffractive axicon with a comparable grating period. Numerical simulation was carried out by the finite differences in the time domain method. It was shown that the direction of change in the height of the relief rings of elements significantly affects the diffraction pattern in the near zone. In particular, for a super-Gaussian beam, the use of a direct ring grating made it possible to reduce the size of the focal spot by 18.7% for radial polarization ('sigma'=5 μm), the use of a reverse ring grating led to a decrease in the focal spot by 36.9% ('sigma'=12.25 µm) in comparison with the action of a diffractive axicon. It was also shown in the paper that when the reverse ring grating is illuminated by the Laguerre-superGauss (1,0) mode with circular polarization, the formation of a narrow and extended region of reduced intensity on the optical axis (optical trap) is observed.
first_indexed 2024-03-13T03:04:12Z
format Article
id doaj.art-ed94df7a888b4b0283dd9a58e578cbd1
institution Directory Open Access Journal
issn 0134-2452
2412-6179
language English
last_indexed 2024-03-13T03:04:12Z
publishDate 2022-08-01
publisher Samara National Research University
record_format Article
series Компьютерная оптика
spelling doaj.art-ed94df7a888b4b0283dd9a58e578cbd12023-06-27T09:42:12ZengSamara National Research UniversityКомпьютерная оптика0134-24522412-61792022-08-0146453754610.18287/2412-6179-CO-1131Peculiarities of focusing circularly and radially polarized super-Gaussian beams using ring gratings with varying relief heightD.A. Savelyev0IPSI RAS – Branch of the FSRC "Crystallography and Photonics" RAS; Samara National Research UniversityThe focusing features of a super-Gaussian beam, as well as Laguerre-super-Gaussian (1,0) modes with radial and circular polarizations on ring gratings (direct and inverse) with a variable height of individual relief rings were investigated in this paper. The change in the height of the relief from the maximum height in the center to the minimum at the edges of the element (direct ring grating) is considered and the reverse case, when the maximum height of the relief was at the edges and the minimum in the center (reverse ring grating). The comparison was carried out with the action of a diffractive axicon with a comparable grating period. Numerical simulation was carried out by the finite differences in the time domain method. It was shown that the direction of change in the height of the relief rings of elements significantly affects the diffraction pattern in the near zone. In particular, for a super-Gaussian beam, the use of a direct ring grating made it possible to reduce the size of the focal spot by 18.7% for radial polarization ('sigma'=5 μm), the use of a reverse ring grating led to a decrease in the focal spot by 36.9% ('sigma'=12.25 µm) in comparison with the action of a diffractive axicon. It was also shown in the paper that when the reverse ring grating is illuminated by the Laguerre-superGauss (1,0) mode with circular polarization, the formation of a narrow and extended region of reduced intensity on the optical axis (optical trap) is observed.https://computeroptics.ru/eng/KO/Annot/KO46-4/460404e.htmlring gratingssuper-gaussian beamlaguerre-super-gaussian (10) modessharp focusingfdtddiffractive axiconoptical trap
spellingShingle D.A. Savelyev
Peculiarities of focusing circularly and radially polarized super-Gaussian beams using ring gratings with varying relief height
Компьютерная оптика
ring gratings
super-gaussian beam
laguerre-super-gaussian (1
0) modes
sharp focusing
fdtd
diffractive axicon
optical trap
title Peculiarities of focusing circularly and radially polarized super-Gaussian beams using ring gratings with varying relief height
title_full Peculiarities of focusing circularly and radially polarized super-Gaussian beams using ring gratings with varying relief height
title_fullStr Peculiarities of focusing circularly and radially polarized super-Gaussian beams using ring gratings with varying relief height
title_full_unstemmed Peculiarities of focusing circularly and radially polarized super-Gaussian beams using ring gratings with varying relief height
title_short Peculiarities of focusing circularly and radially polarized super-Gaussian beams using ring gratings with varying relief height
title_sort peculiarities of focusing circularly and radially polarized super gaussian beams using ring gratings with varying relief height
topic ring gratings
super-gaussian beam
laguerre-super-gaussian (1
0) modes
sharp focusing
fdtd
diffractive axicon
optical trap
url https://computeroptics.ru/eng/KO/Annot/KO46-4/460404e.html
work_keys_str_mv AT dasavelyev peculiaritiesoffocusingcircularlyandradiallypolarizedsupergaussianbeamsusingringgratingswithvaryingreliefheight