{"id":70571,"date":"2024-09-12T14:46:34","date_gmt":"2024-09-12T12:46:34","guid":{"rendered":"https:\/\/www.iemn.fr\/?p=70571"},"modified":"2024-09-12T14:46:34","modified_gmt":"2024-09-12T12:46:34","slug":"these-elodie-carneiro-optimization-of-gan-on-silicon-technology-for-rf-power-applications-2","status":"publish","type":"post","link":"https:\/\/www.iemn.fr\/en\/a-la-une\/these-elodie-carneiro-optimization-of-gan-on-silicon-technology-for-rf-power-applications-2.html","title":{"rendered":"THESIS Huu Thoai Ngo: \"Optical and Electronic Properties of Colloidal CdSe Nanoplatelets and Related Heterostructures\"."},"content":{"rendered":"<div id='layer_slider_1'  class='avia-layerslider main_color avia-shadow  avia-builder-el-0  el_before_av_heading  avia-builder-el-first  container_wrap sidebar_right'  style='height: 261px;'  ><div id=\"layerslider_58_7pwsxmb6v99f\" data-ls-slug=\"homepageslider\" class=\"ls-wp-container fitvidsignore ls-selectable\" 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style=\"font-size:14px;text-align:left;font-style:normal;text-decoration:none;text-transform:none;font-weight:700;letter-spacing:0px;border-style:solid;border-color:#000;background-position:0% 0%;background-repeat:no-repeat;width:180px;height:30px;left:0px;top:231px;line-height:32px;color:#ffffff;border-radius:6px 6px 6px 6px;padding-left:50px;background-color:rgba(0, 0, 0, 0.57);\" class=\"ls-l ls-ib-icon ls-text-layer\" data-ls=\"minfontsize:0;minmobilefontsize:0;\"><i class=\"fa fa-quote-right\" style=\"color:#ffffff;margin-right:0.8em;font-size:1em;transform:translateY( -0.125em );\"><\/i>ACTUALITES<\/ls-layer><\/div><\/div><\/div><div id='after_layer_slider_1'  class='main_color av_default_container_wrap container_wrap sidebar_right'  ><div class='container av-section-cont-open' ><div class='template-page content  av-content-small alpha units'><div class='post-entry post-entry-type-page post-entry-70571'><div class='entry-content-wrapper clearfix'>\n\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-lxd0gkm3-cdaefc273c1b57667ddadcf8449e43bf\">\n#top .av-special-heading.av-lxd0gkm3-cdaefc273c1b57667ddadcf8449e43bf{\nmargin:0 0 10px 0;\npadding-bottom:4px;\n}\nbody .av-special-heading.av-lxd0gkm3-cdaefc273c1b57667ddadcf8449e43bf .av-special-heading-tag .heading-char{\nfont-size:25px;\n}\n.av-special-heading.av-lxd0gkm3-cdaefc273c1b57667ddadcf8449e43bf .av-subheading{\nfont-size:15px;\n}\n<\/style>\n<div  class='av-special-heading av-lxd0gkm3-cdaefc273c1b57667ddadcf8449e43bf av-special-heading-h2  avia-builder-el-1  el_after_av_layerslider  el_before_av_hr  avia-builder-el-first  av-linked-heading'><h2 class='av-special-heading-tag'  itemprop=\"headline\"  >THESE Huu Thoai Ngo : Optical and Electronic Properties of Colloidal CdSe Nanoplatelets and Related Heterostructures<span class='special_amp'>\"<\/span><\/h2><div class=\"special-heading-border\"><div class=\"special-heading-inner-border\"><\/div><\/div><\/div>\n\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-18u73nj-dad6a947580930e400fc42ba200e80f1\">\n#top .hr.av-18u73nj-dad6a947580930e400fc42ba200e80f1{\nmargin-top:5px;\nmargin-bottom:5px;\n}\n.hr.av-18u73nj-dad6a947580930e400fc42ba200e80f1 .hr-inner{\nwidth:100%;\n}\n<\/style>\n<div  class='hr av-18u73nj-dad6a947580930e400fc42ba200e80f1 hr-custom  avia-builder-el-2  el_after_av_heading  el_before_av_textblock  hr-left hr-icon-no'><span class='hr-inner inner-border-av-border-thin'><span class=\"hr-inner-style\"><\/span><\/span><\/div>\n<section  class='av_textblock_section av-jriy64i8-fd5f2e9d63bf552d6910d12f255eb26e'   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/BlogPosting\" itemprop=\"blogPost\" ><div class='avia_textblock'  itemprop=\"text\" >\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-13ewzjw-68e036126b913e5028f77311dc66b825\">\n.av_font_icon.av-13ewzjw-68e036126b913e5028f77311dc66b825{\ncolor:#bfbfbf;\nborder-color:#bfbfbf;\n}\n.av_font_icon.av-13ewzjw-68e036126b913e5028f77311dc66b825 .av-icon-char{\nfont-size:60px;\nline-height:60px;\n}\n<\/style>\n<span  class='av_font_icon av-13ewzjw-68e036126b913e5028f77311dc66b825 avia_animate_when_visible av-icon-style- avia-icon-pos-left avia-icon-animate'><span class='av-icon-char' aria-hidden='true' data-av_icon='\ue8c9' data-av_iconfont='entypo-fontello' ><\/span><\/span>\n<p>Huu Thoai Ngo<\/p>\n<p><strong>17 September 2024 10.00 am<br \/>\n<\/strong>Amphitheatre of the IEMN-Laboratoire central - Villeneuve d'Ascq<\/p>\n<\/div><\/section>\n<section  class='av_textblock_section av-jtefqx33-26fa44c544b10063385818eda37e027b'   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/BlogPosting\" itemprop=\"blogPost\" ><div class='avia_textblock'  itemprop=\"text\" ><div  class='hr av-kjh3zw-4dff888f744b728a1aca9b3a0971493a hr-default  avia-builder-el-6  avia-builder-el-no-sibling'><span class='hr-inner'><span class=\"hr-inner-style\"><\/span><\/span><\/div>\n<h5><strong><span style=\"color: #800000;\">Jury :<\/span><\/strong><\/h5>\n<p><b><u>Supervisors:<\/u><\/b><br \/>\nDr. Louis BIADALA (IEMN - CNRS) - Director of thesis<br \/>\nProf. Iwan MOREELS (PCN group, Ghent University) - Co-supervisor<\/p>\n<p><b><u>The committee consists of:<\/u><\/b><br \/>\nDr. Bruno GRANDIDIER (IEMN-CNRS) - Committee President<br \/>\nDr. Amandine BELLEC (MPQ - CNRS, Paris Cit\u00e9 University) - Reviewer<br \/>\nProf. Sandrine ITHURRIA (ESPCI-Paris, PSL Research University, Sorbonne)<br \/>\nUniversity) - Reviewer<br \/>\nDr. Benoit MAHLER (ILM - Claude Bernard Lyon 1 University) - Examiner<br \/>\nProf. Jean-Pierre HERMIER (University of Versailles St-Quentin-en-Yvelines) - Examiner<br \/>\nProf. Jolien DENDOOVEN (Ghent University) - Examiner<\/p>\n<h5>Summary:<\/h5>\n<p><i>Colloidal nanoplatelets (NPLs) (e.g. CdSe, PbSe) are an interesting class of nanomaterials, which have attracted considerable attention due to the combination of their specific shape with unique electronic properties.<\/i> <i>For example, CdSe LNPs exhibit a strong quantum confinement effect along the thickness, resulting in tunable optoelectronic properties.<\/i> <i>However, colloidal NPLs contain numerous surface defects caused by structural flaws and unpassivated dangling bonds (DBs), which greatly reduce the quantum efficiency of PL.<\/i> <i>Not all dangling links are detrimental to potential NPL applications.<\/i> <i>Surface DB spins have been shown to modify the optical and magnetic properties of CdSe NPLs, via their interactions with a localised electron spin in the NPLs.<\/i> <i>These spin interactions give rise to interesting magneto-optical effects in CdSe NPLs.<\/i> <i>To exploit NPLs in optoelectronic applications, an in-depth understanding of their fundamental properties, at the scale of an individual nanocrystal, is required.<\/i> <i>In this thesis, we used low-temperature scanning tunneling microscopy (LT-STM) and spectroscopy (STS) to study the structural and electronic properties of individual NPLs at the nanoscale.<\/i> <i>In addition, we used magneto-photoluminescence (PL) spectroscopy to study the optical properties of CdSe and CdSe\/CdS core\/crown.<\/i> <i>The results obtained provide an insight into the structure of electronic bands (e.g. band gap, defect states, etc.) and the optical properties of NPLs, in particular quantum confinement and magneto-optical effects.<\/i><\/p>\n<h5>Abstract:<\/h5>\n<p><i>Colloidal nanoplatelets (NPLs) (e.g. CdSe, PbSe) are an interesting class of nanomaterials, that have attracted considerable attention due to the combination of their specific shape with unique electronic properties. For example, CdSe NPLs exhibit a strong quantum confinement effect along the thickness, resulting in tunable optoelectronic properties. However, colloidal NPLs contain many surface defects caused by structural defects and unpassivated dangling bonds (DBs), which strongly reduces the PL quantum efficiency. Not all dangling bonds are harmful to the potential applications of NPLs. Surface DB spins have been shown to alter the optical and magnetic properties of CdSe NPLs, via their interactions with an electron spin localized in NPLs. These spin interactions cause interesting magneto-optical effects in CdSe NPLs. To exploit NPLs in optoelectronic applications, a deep understanding of their fundamental properties, at the scale of an individual nanocrystal, is necessary. In this thesis, we used low-temperature scanning tunneling microscopy (LT-STM) and spectroscopy (STS) to investigate the structural and electronic properties of individual NPLs at the nanoscale. In addition, we used magneto-photoluminescence (PL) spectroscopy to investigate the optical properties of CdSe and CdSe\/CdS core\/crown NPLs. The obtained results provide insight into the electronic band structure (e.g. band gap, defect states...) and optical properties of NPLs, in particular quantum confinement and magneto-optical effects.<\/i><\/p>\n<\/div><\/section>","protected":false},"excerpt":{"rendered":"","protected":false},"author":20,"featured_media":69361,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3,87,65,84],"tags":[],"class_list":["post-70571","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-a-la-une","category-agenda-en","category-agenda","category-agenda-en-en"],"_links":{"self":[{"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/posts\/70571","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/users\/20"}],"replies":[{"embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/comments?post=70571"}],"version-history":[{"count":0,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/posts\/70571\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/media\/69361"}],"wp:attachment":[{"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/media?parent=70571"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/categories?post=70571"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/tags?post=70571"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}