Linear-frequency conversion with time-varying metasurfaces

Autor: Claude Amra, Ali Passian, Philippe Tchamitchian, Mauro Ettorre, Ahmed Alwakil, Juan Antonio Zapien, Paul Rouquette, Yannick Abautret, Myriam Zerrad

Publikováno v: Physical Review Research, Vol 6, Iss 1, p 013002 (2024)

Frequency conversion is a hallmark of nonlinearity. The spectral manifestations, emergent within a system, can typically be attributed to a marked nonlinearity within the material properties, complex geometric configurations, and/or the unique functi

Externí odkaz: https://doaj.org/article/81c65f2a56ad471783e81a693505ede2

Analysis of the multilayer organization of a sunflower leaf during dehydration with terahertz time-domain spectroscopy

Autor: Yannick Abautret, Dominique Coquillat, Michel Lequime, Myriam Zerrad, Claude Amra

Publikováno v: Optics Express
Optics Express, 2022, 30 (21), pp.37971. ⟨10.1364/oe.463228⟩
Optics Express, Optical Society of America-OSA Publishing, 2022, 30 (21), pp.37971. ⟨10.1364/OE.463228⟩

International audience; We apply reverse engineering techniques (RET) to analyze the dehydration process of a sunflower leaf with terahertz time-domain spectroscopy. The multilayer structure of the leaf is extracted with accuracy during the entire pr

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::1cf030e56471113bd4e3869d19ee78bd
https://hal.science/hal-03869090/document

Thin film terahertz reverse engineering to analyse vegetal tissues

Autor: Xavier Buet, Claude Amra, Bruno Grezes-Besset, Daphné Héran, Ryad Bendoula, Yannick Abautret, Frédéric Chazallet, Gabriel Soriano, Myriam Zerrad, Dominique Coquillat

Publikováno v: Proc. SPIE 11872, Advances in Optical Thin Films VII, 1187209 (12 September 2021)
SPIE OPTICAL SYSTEMS DESIGN
SPIE OPTICAL SYSTEMS DESIGN, Sep 2021, Madrid, Spain. ⟨10.1117/12.2597056⟩

International audience; Thin film techniques also find applications outside their classical sectors, and among them is the terahertz field. These waves allow to penetrate a large variety of materials opaque to optics, and find applications in securit

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::eca027f46aa0f06058f07f2a35424565
https://hal.archives-ouvertes.fr/hal-03413162

Optical thickness of a plant leaf measured with THz pulse echoes

Autor: Frédéric Chazallet, Ryad Bendoula, Claude Amra, Bruno Grezes-Besset, Yannick Abautret, Daphné Héran, Gabriel Soriano, Myriam Zerrad, Dominique Coquillat

Publikováno v: Proceedings of SPIE
TERAHERTZ, RF, MILLIMETER, AND SUBMILLIMETER-WAVE TECHNOLOGY AND APPLICATIONS XIII, 2020
TERAHERTZ, RF, MILLIMETER, AND SUBMILLIMETER-WAVE TECHNOLOGY AND APPLICATIONS XIII, 2020, 2020, San Francisco, United States. pp.112790L, ⟨10.1117/12.2543710⟩

We analyze Terahertz (THz) echoes by reflection on a sunflower leaf in order to evaluate the internal leaf structure (geometry, complex indices and thicknesses). The analysis is based on the thin film multilayer formalism in time and frequency domain

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::82609a42226d8761398cb6d085502abb
https://hal.inrae.fr/hal-02978005

Adaptive optics with programmable Fourier-based wavefront sensors: a spatial light modulator approach to the LAM/ONERA on-sky pyramid sensor testbed

Autor: Yannick Abautret, Benoit Neichel, Kjetil Dohlen, Thierry Fusco, Charlotte Z. Bond, Kacem El-Hadi, Olivier Fauvarque, Lauren Schatz, Carlos Correia, Jean-François Sauvage, P. Janin-Potiron, Vincent Chambouleyron, Eduard Muslimov

Publikováno v: Journal of Astronomical Telescopes Instruments and Systems
Journal of Astronomical Telescopes Instruments and Systems, Society of Photo-optical Instrumentation Engineers, 2019, 5 (03), pp.1. ⟨10.1117/1.JATIS.5.3.039001⟩

International audience; Wavefront sensors encode phase information of an incoming wavefront into an intensity pattern that can be measured on a camera. Several kinds of wavefront sensors (WFS) are used in astronomical adaptive optics. Amongst them, F

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::0d81be97dd31d9f3aa0b337193a21b78
https://hal.archives-ouvertes.fr/hal-02361237