{"id":11788,"date":"2025-12-08T15:47:15","date_gmt":"2025-12-08T14:47:15","guid":{"rendered":"https:\/\/www.institut-foton.eu\/?p=11788"},"modified":"2025-12-10T12:02:28","modified_gmt":"2025-12-10T11:02:28","slug":"these-youssef-ghandaoui-17-12-2025","status":"publish","type":"post","link":"https:\/\/www.institut-foton.eu\/en\/these-youssef-ghandaoui-17-12-2025\/","title":{"rendered":"Th\u00e8se &#8211; Youssef GHANDAOUI &#8211; 17\/12\/2025"},"content":{"rendered":"\n<p><strong>L\u2019Institut Foton vous convie \u00e0 la pr\u00e9sentation des travaux de th\u00e8se de doctorat :<\/strong><\/p>\n\n\n\n<p class=\"has-text-align-center has-medium-font-size\"><br><strong><em>Verres de chalcog\u00e9nures sans arsenic pour la photonique int\u00e9gr\u00e9e infrarouge non lin\u00e9aire.<\/em><\/strong><\/p>\n\n\n\n<p><\/p>\n\n\n\n<p class=\"has-text-align-center has-vivid-cyan-blue-color has-text-color has-link-color wp-elements-27bf490b9269b30c92b5a5e5f0d47e83\">Youssef GHANDAOUI<\/p>\n\n\n\n<p>sous la direction de Virginie Nazabal, Jo\u00ebl Charrier et Lucas Deniel<\/p>\n\n\n\n<p><strong>Cette soutenance publique aura lieu le<\/strong> <strong>mercredi 17 d\u00e9cembre \u00e0 9h30,&nbsp;Campus de Beaulieu, Rennes \u2013 amphi A (Ren\u00e9 Dabard) b\u00e2timent B02A<\/strong><\/p>\n\n\n\n<p>Assister \u00e0 la soutenance par visioconf\u00e9rence Big Blue Button :<\/p>\n\n\n\n<p><a href=\"https:\/\/bbb.univ-rennes.fr\/rooms\/5qu-o8v-rhm-5gn\/join\">https:\/\/bbb.univ-rennes.fr\/rooms\/5qu-o8v-rhm-5gn\/join<\/a><\/p>\n\n\n\n<p><\/p>\n\n\n\n<p><\/p>\n\n\n\n<p><strong>Composition du Jury&nbsp;:<\/strong><\/p>\n\n\n\n<p><strong>Rapporteurs avant soutenance&nbsp;<\/strong>:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Julien Lumeau (Directeur de Recherche CNRS, Institut Fresnel, Aix-Marseille Universit\u00e9)<\/li>\n\n\n\n<li>S\u00e9bastien Cueff (Charg\u00e9 de Recherche CNRS, INL, Universit\u00e9 de Lyon)<\/li>\n<\/ul>\n\n\n\n<p><br><strong>Examinateurs<\/strong>&nbsp;:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>V\u00e9ronique Bardinal (Directrice de Recherches, CNRS, LAAS, Universit\u00e9 de Toulouse)<\/li>\n\n\n\n<li>Ang\u00e9line Poulon (Ma\u00eetresse de conf\u00e9rences, ICMCB, Universit\u00e9 de Bordeaux)<\/li>\n<\/ul>\n\n\n\n<p><strong>Dir. de th\u00e8se&nbsp;:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Virginie Nazabal (Directrice de Recherche CNRS, ISCR, Universit\u00e9 de Rennes)<\/li>\n<\/ul>\n\n\n\n<p><strong>Co-dir. de th\u00e8se&nbsp;:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Jo\u00ebl Charrier (Professeur des Universit\u00e9s, Institut Foton, Universit\u00e9 de Rennes)<\/li>\n<\/ul>\n\n\n\n<p><strong>Encadrant&nbsp;:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Lucas Deniel (Ma\u00eetre de conf\u00e9rences, Institut Foton, Universit\u00e9 de Rennes)<\/li>\n<\/ul>\n\n\n\n<p><strong>Invit\u00e9s&nbsp;:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Mehdi Alouini (Professeur des Universit\u00e9s, Institut Foton &#8211; IETR, Universit\u00e9 de Rennes)<\/li>\n\n\n\n<li>Stanislav Pechev (Ing\u00e9nieur de Recherches, CNRS, ICMCB, Universit\u00e9 de Bordeaux)<\/li>\n<\/ul>\n\n\n\n<p><\/p>\n\n\n\n<p><\/p>\n\n\n\n<p><strong>Mots cl\u00e9s :<\/strong> Verres de chalcog\u00e9nures, couches minces, guides d\u2019onde, optique nonlin\u00e9aire, photonique infrarouge, diffusion de Brillouin stimul\u00e9e (SBS).<\/p>\n\n\n\n<p><strong>R\u00e9sum\u00e9<\/strong><strong> :<\/strong> Le d\u00e9veloppement de mat\u00e9riaux durables pour la photonique int\u00e9gr\u00e9e a motiv\u00e9 l&#8217;exploration de verres chalcog\u00e9nures sans arsenic comme alternatives aux syst\u00e8mes conventionnels \u00e0 base d&#8217;arsenic. Dans ce travail, les compositions Ge-Bi-S, Ge-Bi-Sb-S et Ge-Bi-Se ont \u00e9t\u00e9 \u00e9tudi\u00e9es \u00e0 diff\u00e9rents niveaux, tels que les synth\u00e8ses des verres massifs, les d\u00e9p\u00f4ts de couches minces et les fabrications de guides d&#8217;ondes. Des verres sulfures massifs de diff\u00e9rentes compositions ont \u00e9t\u00e9 synth\u00e9tis\u00e9s par la m\u00e9thode fusion trempe, et caract\u00e9ris\u00e9s \u00e0 l&#8217;aide d&#8217;analyses structurelles (XRD, diffraction neutronique, EXAFS), thermiques et optiques, r\u00e9v\u00e9lant des bandes interdites, des indices de r\u00e9fraction et des coefficients non lin\u00e9aires ajustables directement li\u00e9s \u00e0 la composition.<\/p>\n\n\n\n<p>La co-pulv\u00e9risation RF a \u00e9t\u00e9 utilis\u00e9e pour fabriquer des films minces, qui ont servi \u00e0 la fabrication des guides d&#8217;ondes, gr\u00e2ce \u00e0 des processus de nanofabrication optimis\u00e9s, o\u00f9 des \u00e9tudes syst\u00e9matiques de la gravure, de la rugosit\u00e9 des parois lat\u00e9rales et des pertes par diffusion ont \u00e9t\u00e9 men\u00e9es en d\u00e9tail. Les caract\u00e9risations optiques ont r\u00e9v\u00e9l\u00e9 une transparence infrarouge \u00e0 large bande et de fortes non-lin\u00e9arit\u00e9s de Kerr, tandis que la densit\u00e9 a mis en \u00e9vidence leur potentiel pour des interactions Brillouin efficaces. Une \u00e9tape cl\u00e9 de cette recherche est la premi\u00e8re observation sur puce de la diffusion Brillouin stimul\u00e9e dans des guides d&#8217;ondes Ge-Sb-Se sans arsenic, confirmant ainsi l&#8217;utilisation de mat\u00e9riaux sans arsenic pour la photonique non lin\u00e9aire. Servant de cadre coh\u00e9rent pour des plateformes chalcog\u00e9nures respectueuses de l&#8217;environnement, cette recherche combine la chimie des mat\u00e9riaux, la caract\u00e9risation avanc\u00e9e et l&#8217;int\u00e9gration.<\/p>\n\n\n\n<p><\/p>\n\n\n\n<p><\/p>\n\n\n\n<p><\/p>\n\n\n\n<p><\/p>\n\n\n\n<p class=\"has-text-align-center has-medium-font-size\"><strong>Arsenic-free chalcogenide glasses for nonlinear infrared integrated photonics.<\/strong><\/p>\n\n\n\n<p><strong>Keywords :<\/strong> Chalcogenide glasses, thin films, waveguides, nonlinear optics, infrared photonics, stimulated Brillouin scattering (SBS).<\/p>\n\n\n\n<p><strong>Abstract<\/strong><strong>:<\/strong> The development of safe and sustainable materials for photonic integration has motivated the exploration of arsenic-free chalcogenide glasses as alternatives to conventional As-based systems. In this work, Ge-Bi-S, Ge-Bi-Sb-S, and Ge-Bi-Se compositions were investigated at various levels, such as bulks syntheses, thin films integrations and waveguides fabrications. Bulk sulfide glasses of different compositions were synthesized by melt-quenching and characterized using structural (XRD, neutron diffraction, EXAFS), thermal, and optical analyses, revealing tunable bandgaps, refractive indices, and nonlinear coefficients directly linked to composition and local bonding environments.<\/p>\n\n\n\n<p>RF co-sputtering was used to fabricate thin films, which served for ridge waveguides processing, through optimized nanofabrication processes, where systematic studies of etching, sidewall roughness, and scattering losses were studied in detail. Optical characterizations revealed broadband infrared transparency and strong Kerr nonlinearities, while density highlighted their potential for efficient Brillouin interactions. A key milestone of this research is the first on-chip observation of stimulated Brillouin scattering in arsenic-free Ge-Sb-Se waveguides, thus confirming the use of arsenic-free materials for nonlinear photonics. Serving as a coherent framework for environmentally responsible chalcogenide platforms, this research combines materials chemistry, advanced characterization, and integrated photonics toward compact, efficient, durable devices for near- and mid-infrared application.<\/p>\n\n\n\n<p><\/p>\n","protected":false},"excerpt":{"rendered":"<p>L\u2019Institut Foton vous convie \u00e0 la pr\u00e9sentation des travaux de th\u00e8se de doctorat : Verres de chalcog\u00e9nures sans arsenic pour la photonique int\u00e9gr\u00e9e infrarouge non lin\u00e9aire. Youssef GHANDAOUI sous la direction de Virginie Nazabal, Jo\u00ebl Charrier et Lucas Deniel Cette<\/p>\n","protected":false},"author":11,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"inline_featured_image":false,"footnotes":""},"categories":[37,9],"tags":[],"class_list":["post-11788","post","type-post","status-publish","format-standard","hentry","category-agenda","category-non-classe"],"translation":{"provider":"WPGlobus","version":"3.0.2","language":"en","enabled_languages":["fr","en"],"languages":{"fr":{"title":true,"content":true,"excerpt":false},"en":{"title":false,"content":false,"excerpt":false}}},"_links":{"self":[{"href":"https:\/\/www.institut-foton.eu\/en\/wp-json\/wp\/v2\/posts\/11788","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.institut-foton.eu\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.institut-foton.eu\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.institut-foton.eu\/en\/wp-json\/wp\/v2\/users\/11"}],"replies":[{"embeddable":true,"href":"https:\/\/www.institut-foton.eu\/en\/wp-json\/wp\/v2\/comments?post=11788"}],"version-history":[{"count":3,"href":"https:\/\/www.institut-foton.eu\/en\/wp-json\/wp\/v2\/posts\/11788\/revisions"}],"predecessor-version":[{"id":11793,"href":"https:\/\/www.institut-foton.eu\/en\/wp-json\/wp\/v2\/posts\/11788\/revisions\/11793"}],"wp:attachment":[{"href":"https:\/\/www.institut-foton.eu\/en\/wp-json\/wp\/v2\/media?parent=11788"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.institut-foton.eu\/en\/wp-json\/wp\/v2\/categories?post=11788"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.institut-foton.eu\/en\/wp-json\/wp\/v2\/tags?post=11788"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}