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Spiral sound-diffusing metasurfaces based on holographic vortices
In this work, we show that scattered acoustic vortices generated by metasurfaces with chiral symmetry present broadband unusual properties in the far-field. These metasurfaces are designed to encode the holographic field of an acoustical vortex, resulting in structures with spiral geometry. In the n...
Autores principales: | , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Nature Publishing Group UK
2021
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8119454/ https://www.ncbi.nlm.nih.gov/pubmed/33986336 http://dx.doi.org/10.1038/s41598-021-89487-8 |
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author | Jiménez, Noé Groby, Jean-Philippe Romero-García, Vicent |
author_facet | Jiménez, Noé Groby, Jean-Philippe Romero-García, Vicent |
author_sort | Jiménez, Noé |
collection | PubMed |
description | In this work, we show that scattered acoustic vortices generated by metasurfaces with chiral symmetry present broadband unusual properties in the far-field. These metasurfaces are designed to encode the holographic field of an acoustical vortex, resulting in structures with spiral geometry. In the near field, phase dislocations with tuned topological charge emerge when the scattered waves interference destructively along the axis of the spiral metasurface. In the far field, metasurfaces based on holographic vortices inhibit specular reflections because all scattered waves also interfere destructively in the normal direction. In addition, the scattering function in the far field is unusually uniform because the reflected waves diverge spherically from the holographic focal point. In this way, by triggering vorticity, energy can be evenly reflected in all directions except to the normal. As a consequence, the designed metasurface presents a mean correlation-scattering coefficient of 0.99 (0.98 in experiments) and a mean normalized diffusion coefficient of 0.73 (0.76 in experiments) over a 4 octave frequency band. The singular features of the resulting metasurfaces with chiral geometry allow the simultaneous generation of broadband, diffuse and non-specular scattering. These three exceptional features make spiral metasurfaces extraordinary candidates for controlling acoustic scattering and generating diffuse sound reflections in several applications and branches of wave physics as underwater acoustics, biomedical ultrasound, particle manipulation devices or room acoustics. |
format | Online Article Text |
id | pubmed-8119454 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2021 |
publisher | Nature Publishing Group UK |
record_format | MEDLINE/PubMed |
spelling | pubmed-81194542021-05-14 Spiral sound-diffusing metasurfaces based on holographic vortices Jiménez, Noé Groby, Jean-Philippe Romero-García, Vicent Sci Rep Article In this work, we show that scattered acoustic vortices generated by metasurfaces with chiral symmetry present broadband unusual properties in the far-field. These metasurfaces are designed to encode the holographic field of an acoustical vortex, resulting in structures with spiral geometry. In the near field, phase dislocations with tuned topological charge emerge when the scattered waves interference destructively along the axis of the spiral metasurface. In the far field, metasurfaces based on holographic vortices inhibit specular reflections because all scattered waves also interfere destructively in the normal direction. In addition, the scattering function in the far field is unusually uniform because the reflected waves diverge spherically from the holographic focal point. In this way, by triggering vorticity, energy can be evenly reflected in all directions except to the normal. As a consequence, the designed metasurface presents a mean correlation-scattering coefficient of 0.99 (0.98 in experiments) and a mean normalized diffusion coefficient of 0.73 (0.76 in experiments) over a 4 octave frequency band. The singular features of the resulting metasurfaces with chiral geometry allow the simultaneous generation of broadband, diffuse and non-specular scattering. These three exceptional features make spiral metasurfaces extraordinary candidates for controlling acoustic scattering and generating diffuse sound reflections in several applications and branches of wave physics as underwater acoustics, biomedical ultrasound, particle manipulation devices or room acoustics. Nature Publishing Group UK 2021-05-13 /pmc/articles/PMC8119454/ /pubmed/33986336 http://dx.doi.org/10.1038/s41598-021-89487-8 Text en © The Author(s) 2021 https://creativecommons.org/licenses/by/4.0/Open AccessThis article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/ (https://creativecommons.org/licenses/by/4.0/) . |
spellingShingle | Article Jiménez, Noé Groby, Jean-Philippe Romero-García, Vicent Spiral sound-diffusing metasurfaces based on holographic vortices |
title | Spiral sound-diffusing metasurfaces based on holographic vortices |
title_full | Spiral sound-diffusing metasurfaces based on holographic vortices |
title_fullStr | Spiral sound-diffusing metasurfaces based on holographic vortices |
title_full_unstemmed | Spiral sound-diffusing metasurfaces based on holographic vortices |
title_short | Spiral sound-diffusing metasurfaces based on holographic vortices |
title_sort | spiral sound-diffusing metasurfaces based on holographic vortices |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8119454/ https://www.ncbi.nlm.nih.gov/pubmed/33986336 http://dx.doi.org/10.1038/s41598-021-89487-8 |
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