Cargando…

Laser–Material Interactions of High-Quality Ultrashort Pulsed Vector Vortex Beams

Diffractive multi-beams based on 1 × 5 and 2 × 2 binary Dammann gratings applied to a spatial light modulator (SLM) combined with a nanostructured S-wave plate have been used to generate uniform multiple cylindrical vector beams with radial and azimuthal polarizations. The vector quality factor (con...

Descripción completa

Detalles Bibliográficos
Autores principales: Tang, Yue, Perrie, Walter, Rico Sierra, David, Li, Qianliang, Liu, Dun, Edwardson, Stuart P., Dearden, Geoff
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8065781/
https://www.ncbi.nlm.nih.gov/pubmed/33915722
http://dx.doi.org/10.3390/mi12040376
_version_ 1783682421083865088
author Tang, Yue
Perrie, Walter
Rico Sierra, David
Li, Qianliang
Liu, Dun
Edwardson, Stuart P.
Dearden, Geoff
author_facet Tang, Yue
Perrie, Walter
Rico Sierra, David
Li, Qianliang
Liu, Dun
Edwardson, Stuart P.
Dearden, Geoff
author_sort Tang, Yue
collection PubMed
description Diffractive multi-beams based on 1 × 5 and 2 × 2 binary Dammann gratings applied to a spatial light modulator (SLM) combined with a nanostructured S-wave plate have been used to generate uniform multiple cylindrical vector beams with radial and azimuthal polarizations. The vector quality factor (concurrence) of the single vector vortex beam was found to be C = 0.95 ± 0.02, hence showing a high degree of vector purity. The multi-beams have been used to ablate polished metal samples (Ti-6Al-4V) with laser-induced periodic surface structures (LIPSS), which confirm the polarization states unambiguously. The measured ablation thresholds of the ring mode radial and azimuthal polarizations are close to those of a Gaussian mode when allowance is made for the expected absolute intensity distribution of a ring beam generated from a Gaussian. In addition, ring mode vortex beams with varying orbital angular momentum (OAM) exhibit the same ablation threshold on titanium alloy. Beam scanning with ring modes for surface LIPSS formation can increase micro-structuring throughput by optimizing fluence over a larger effective beam diameter. The comparison of each machined spot was analysed with a machine learning method—cosine similarity—which confirmed the degree of spatial uniformity achieved, reaching cosθ > 0.96 and 0.92 for the 1 × 5 and 2 × 2 arrays, respectively. Scanning electron microscopy (SEM), optical microscopy and white light surface profiling were used to characterize and quantify the effects of surface modification.
format Online
Article
Text
id pubmed-8065781
institution National Center for Biotechnology Information
language English
publishDate 2021
publisher MDPI
record_format MEDLINE/PubMed
spelling pubmed-80657812021-04-25 Laser–Material Interactions of High-Quality Ultrashort Pulsed Vector Vortex Beams Tang, Yue Perrie, Walter Rico Sierra, David Li, Qianliang Liu, Dun Edwardson, Stuart P. Dearden, Geoff Micromachines (Basel) Article Diffractive multi-beams based on 1 × 5 and 2 × 2 binary Dammann gratings applied to a spatial light modulator (SLM) combined with a nanostructured S-wave plate have been used to generate uniform multiple cylindrical vector beams with radial and azimuthal polarizations. The vector quality factor (concurrence) of the single vector vortex beam was found to be C = 0.95 ± 0.02, hence showing a high degree of vector purity. The multi-beams have been used to ablate polished metal samples (Ti-6Al-4V) with laser-induced periodic surface structures (LIPSS), which confirm the polarization states unambiguously. The measured ablation thresholds of the ring mode radial and azimuthal polarizations are close to those of a Gaussian mode when allowance is made for the expected absolute intensity distribution of a ring beam generated from a Gaussian. In addition, ring mode vortex beams with varying orbital angular momentum (OAM) exhibit the same ablation threshold on titanium alloy. Beam scanning with ring modes for surface LIPSS formation can increase micro-structuring throughput by optimizing fluence over a larger effective beam diameter. The comparison of each machined spot was analysed with a machine learning method—cosine similarity—which confirmed the degree of spatial uniformity achieved, reaching cosθ > 0.96 and 0.92 for the 1 × 5 and 2 × 2 arrays, respectively. Scanning electron microscopy (SEM), optical microscopy and white light surface profiling were used to characterize and quantify the effects of surface modification. MDPI 2021-04-01 /pmc/articles/PMC8065781/ /pubmed/33915722 http://dx.doi.org/10.3390/mi12040376 Text en © 2021 by the authors. https://creativecommons.org/licenses/by/4.0/Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Tang, Yue
Perrie, Walter
Rico Sierra, David
Li, Qianliang
Liu, Dun
Edwardson, Stuart P.
Dearden, Geoff
Laser–Material Interactions of High-Quality Ultrashort Pulsed Vector Vortex Beams
title Laser–Material Interactions of High-Quality Ultrashort Pulsed Vector Vortex Beams
title_full Laser–Material Interactions of High-Quality Ultrashort Pulsed Vector Vortex Beams
title_fullStr Laser–Material Interactions of High-Quality Ultrashort Pulsed Vector Vortex Beams
title_full_unstemmed Laser–Material Interactions of High-Quality Ultrashort Pulsed Vector Vortex Beams
title_short Laser–Material Interactions of High-Quality Ultrashort Pulsed Vector Vortex Beams
title_sort laser–material interactions of high-quality ultrashort pulsed vector vortex beams
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8065781/
https://www.ncbi.nlm.nih.gov/pubmed/33915722
http://dx.doi.org/10.3390/mi12040376
work_keys_str_mv AT tangyue lasermaterialinteractionsofhighqualityultrashortpulsedvectorvortexbeams
AT perriewalter lasermaterialinteractionsofhighqualityultrashortpulsedvectorvortexbeams
AT ricosierradavid lasermaterialinteractionsofhighqualityultrashortpulsedvectorvortexbeams
AT liqianliang lasermaterialinteractionsofhighqualityultrashortpulsedvectorvortexbeams
AT liudun lasermaterialinteractionsofhighqualityultrashortpulsedvectorvortexbeams
AT edwardsonstuartp lasermaterialinteractionsofhighqualityultrashortpulsedvectorvortexbeams
AT deardengeoff lasermaterialinteractionsofhighqualityultrashortpulsedvectorvortexbeams