{"id":7854,"date":"2024-02-02T09:15:34","date_gmt":"2024-02-02T08:15:34","guid":{"rendered":"https:\/\/www.uni.lu\/fstm-en\/?post_type=events&#038;p=7854"},"modified":"2024-05-13T14:34:45","modified_gmt":"2024-05-13T12:34:45","slug":"physics-colloqium","status":"publish","type":"events","link":"https:\/\/www.uni.lu\/fstm-en\/events\/physics-colloqium\/","title":{"rendered":"Physics Colloqium"},"content":{"rendered":"\n<section class=\"py-0 wp-block-unilux-blocks-free-section section\"><div class=\"container xl:max-w-screen-xl\">\n<section class=\"wp-block-unilux-blocks-free-section section\"><div class=\"container xl:max-w-screen-xl\">\n<h2 class=\"has-text-align-left wp-block-unilux-blocks-heading\"        id=\"nonlinear-interrogation-of-quantum-materials-why-higher-order-response-tells-you-more\"\n    >\n<strong>Nonlinear interrogation of quantum materials: why higher order response tells you more<\/strong><\/h2>\n<\/div><\/section>\n\n\n\n<section class=\"py-0 wp-block-unilux-blocks-free-section section\"><div class=\"container xl:max-w-screen-xl\">\n<p>The nonlinear response of quantum materials contains a wealth of information that is often hidden in the linear regime. Examples include second-harmonic generation (SHG) as a sensitive probe of electronic symmetry, and higher-order conductivities that provide insights into the quantum geometry of Bloch states and their Berry curvature distribution. Two-dimensional coherent THz and Raman spectroscopy are two other powerful nonlinear probes of low-energy excitations in quantum materials, which have recently become available in several labs. We review experimental progress and introduce an intuitive theoretical description of these methods in terms of Liouville quantum pathways. We then theoretically show how they can directly probe quasiparticle properties in the Kitaev honeycomb spin liquid and provide direct evidence for the emergence of localized Majorana excitations trapped by vison pairs.<\/p>\n\n\n\n<p><strong>About the speaker<\/strong><\/p>\n\n\n\n<p>Peter P. Orth is a theoretical condensed matter physicist who works on understanding and predicting properties of quantum materials. He explores quantum materials in and away from equilibrium using analytical field theory and quantum computing algorithms. Peter P. Orth is currently Professor in the Department of Physics at Saarland University, Germany. He is also Affiliate Associate Professor in the Department of Physics and Astronomy at Iowa State University and Contributing Scientist at Ames Laboratory. He received a Diploma in Physics at the Universit\u00e4t Heidelberg in 2007, and a Ph.D at Yale University in 2011 under the supervision of Prof. Karyn Le Hur. He held postdoctoral positions at the Karlsruhe Institute of Technology (KIT) and at the University of Minnesota. He served as deputy director of the &#8220;Center for the Advancement of Topological Semimetals&#8221; of the U.S. Department of Energy (DOE), where he investigated how to realize desired band topologies by controlling magnetic order and is a co-leader in the quantum algorithm thrust of the DOE National Quantum Initiative Center on &#8220;Superconducting Quantum Materials and Systems&#8221; (SQMS), where he develops and implements quantum computing algorithms for many-body systems.<\/p>\n\n\n\n<p>This year, the physics colloquium has a <strong>new format<\/strong>:<\/p>\n\n\n\n<ul class=\"ulux-list\">\n<li class=\"ulux-list-item\">Onsite at Campus Limpertsberg,\u00a0 where you will have the opportunity to <em><strong>meet the speaker over lunch<\/strong><\/em>. The catering is offered only to the registered participants from noon in the BSC Hall.<\/li>\n\n\n\n<li class=\"ulux-list-item\">Online \u2013 through Webex \u2013 to allow you to listen to the talk in case you are travelling or cannot make it on-site at Campus Limpertsberg.<\/li>\n<\/ul>\n\n\n\n<ul class=\"wp-block-unilux-blocks-custom-buttons btn-list\"><li class=\"wp-block-unilux-blocks-custom-button\"    aria-disabled=\"false\"\n    >\n    <a\n        role=\"link\"\n        aria-disabled=\"false\"\n                    href=\"https:\/\/unilu.webex.com\/wbxmjs\/joinservice\/sites\/unilu\/meeting\/download\/c8440db57d2f47a7aa2df1a7ea6c55ec?siteurl=unilu&#038;MTID=m6323da275dbfc5e9902c0b1f1de837a2\"\n                target=\"_blank\"\n        class=\"btn btn--primary\"\n            >Join webinar<\/a>\n<\/li>\n<\/ul>\n\n\n<div class=\"wp-block-unilux-blocks-spacer is-spacer-size-sm\"><\/div>\n\n\n<p>Meeting number: 2780 938 4373<\/p>\n\n\n\n<p>Meeting password: 6aKyDHDDU86<\/p>\n\n\n\n<p><strong>Registration<\/strong><\/p>\n\n\n\n<p>Please register for the lunch before 14 February 2024.<\/p>\n\n\n\n<ul class=\"wp-block-unilux-blocks-custom-buttons btn-list\"><li class=\"wp-block-unilux-blocks-custom-button\"    aria-disabled=\"false\"\n    >\n    <a\n        role=\"link\"\n        aria-disabled=\"false\"\n                    href=\"https:\/\/ulsurvey.uni.lu\/index.php\/486581?lang=en.\"\n                target=\"_blank\"\n        class=\"btn btn--primary\"\n            >Register<\/a>\n<\/li>\n<\/ul>\n<\/div><\/section>\n<\/div><\/section>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":52,"featured_media":7863,"parent":0,"menu_order":0,"comment_status":"open","ping_status":"closed","template":"","format":"standard","meta":{"featured_image_focal_point":[],"show_featured_caption":false,"ulux_newsletter_groups":"","uluxPostTitle":"","uluxPrePostTitle":"","_trash_the_other_posts":false,"_price":"","_stock":"","_tribe_ticket_header":"","_tribe_default_ticket_provider":"","_tribe_ticket_capacity":"0","_ticket_start_date":"","_ticket_end_date":"","_tribe_ticket_show_description":"","_tribe_ticket_show_not_going":false,"_tribe_ticket_use_global_stock":"","_tribe_ticket_global_stock_level":"","_global_stock_mode":"","_global_stock_cap":"","_tribe_rsvp_for_event":"","_tribe_ticket_going_count":"","_tribe_ticket_not_going_count":"","_tribe_tickets_list":"[]","_tribe_ticket_has_attendee_info_fields":false,"event_start_date":"2024-02-21 13:00:00","event_end_date":"2024-02-21 14:00:00","event_speaker_name":"Prof. Peter P. Orth ","event_speaker_link":"","event_is_online":false,"event_location":"B\u00e2timent des Sciences, Room BS 0.03","event_street":"162 Av de la Faiencerie ","event_location_link":"","event_zip_code":"1511","event_city":"Luxemburg","event_country":"Luxembourg"},"events-topic":[],"events-type":[329,322],"organisation":[80,29],"authorship":[52],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v22.3 (Yoast SEO v22.3) - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>Physics Colloqium - FSTM events I Uni.lu<\/title>\n<meta name=\"description\" content=\"The nonlinear response of quantum materials contains a wealth of information that is often hidden in the linear regime. Examples include second-harmonic\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.uni.lu\/fstm-en\/events\/physics-colloqium\/\" \/>\n<meta property=\"og:locale\" content=\"en_GB\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Physics Colloqium\" \/>\n<meta property=\"og:description\" content=\"The nonlinear response of quantum materials contains a wealth of information that is often hidden in the linear regime. Examples include second-harmonic\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.uni.lu\/fstm-en\/events\/physics-colloqium\/\" \/>\n<meta property=\"og:site_name\" content=\"FSTM EN\" \/>\n<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/fstm.uni.lu\/\" \/>\n<meta property=\"article:modified_time\" content=\"2024-05-13T12:34:45+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/www.uni.lu\/wp-content\/uploads\/sites\/4\/2024\/02\/Peter_Orth.jpg\" \/>\n\t<meta property=\"og:image:width\" content=\"792\" \/>\n\t<meta property=\"og:image:height\" content=\"792\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/jpeg\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Estimated reading time\" \/>\n\t<meta name=\"twitter:data1\" content=\"2 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.uni.lu\/fstm-en\/events\/physics-colloqium\/\",\"url\":\"https:\/\/www.uni.lu\/fstm-en\/events\/physics-colloqium\/\",\"name\":\"Physics Colloqium - FSTM events I Uni.lu\",\"isPartOf\":{\"@id\":\"https:\/\/www.uni.lu\/fstm-en\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\/\/www.uni.lu\/fstm-en\/events\/physics-colloqium\/#primaryimage\"},\"image\":{\"@id\":\"https:\/\/www.uni.lu\/fstm-en\/events\/physics-colloqium\/#primaryimage\"},\"thumbnailUrl\":\"https:\/\/www.uni.lu\/wp-content\/uploads\/sites\/4\/2024\/02\/Peter_Orth.jpg\",\"datePublished\":\"2024-02-02T08:15:34+00:00\",\"dateModified\":\"2024-05-13T12:34:45+00:00\",\"description\":\"The nonlinear response of quantum materials contains a wealth of information that is often hidden in the linear regime. Examples include second-harmonic\",\"breadcrumb\":{\"@id\":\"https:\/\/www.uni.lu\/fstm-en\/events\/physics-colloqium\/#breadcrumb\"},\"inLanguage\":\"en-GB\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/www.uni.lu\/fstm-en\/events\/physics-colloqium\/\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"en-GB\",\"@id\":\"https:\/\/www.uni.lu\/fstm-en\/events\/physics-colloqium\/#primaryimage\",\"url\":\"https:\/\/www.uni.lu\/wp-content\/uploads\/sites\/4\/2024\/02\/Peter_Orth.jpg\",\"contentUrl\":\"https:\/\/www.uni.lu\/wp-content\/uploads\/sites\/4\/2024\/02\/Peter_Orth.jpg\",\"width\":792,\"height\":792},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/www.uni.lu\/fstm-en\/events\/physics-colloqium\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/www.uni.lu\/en\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Faculty of Science, Technology and Medicine\",\"item\":\"https:\/\/www.uni.lu\/fstm-en\/\"},{\"@type\":\"ListItem\",\"position\":3,\"name\":\"Events\",\"item\":\"https:\/\/www.uni.lu\/fstm-en\/events\/\"},{\"@type\":\"ListItem\",\"position\":4,\"name\":\"Physics Colloqium\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/www.uni.lu\/fstm-en\/#website\",\"url\":\"https:\/\/www.uni.lu\/fstm-en\/\",\"name\":\"FSTM\",\"description\":\"Faculty of Science, Technology and Medicine I Uni.lu\",\"publisher\":{\"@id\":\"https:\/\/www.uni.lu\/fstm-en\/#organization\"},\"alternateName\":\"Faculty of Science, Technology and Medicine I University of Luxembourg\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/www.uni.lu\/fstm-en\/?s={search_term_string}\"},\"query-input\":\"required name=search_term_string\"}],\"inLanguage\":\"en-GB\"},{\"@type\":\"Organization\",\"@id\":\"https:\/\/www.uni.lu\/fstm-en\/#organization\",\"name\":\"FSTM - University of Luxembourg I Uni.lu\",\"alternateName\":\"Faculty of Science, Technology and Medicine\",\"url\":\"https:\/\/www.uni.lu\/fstm-en\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-GB\",\"@id\":\"https:\/\/www.uni.lu\/fstm-en\/#\/schema\/logo\/image\/\",\"url\":\"https:\/\/www.uni.lu\/wp-content\/uploads\/sites\/4\/2026\/03\/03111650\/FSTM_SM-Profile_1600x1600px-scaled.jpg\",\"contentUrl\":\"https:\/\/www.uni.lu\/wp-content\/uploads\/sites\/4\/2026\/03\/03111650\/FSTM_SM-Profile_1600x1600px-scaled.jpg\",\"width\":2560,\"height\":2560,\"caption\":\"FSTM - University of Luxembourg I Uni.lu\"},\"image\":\"https:\/\/www.uni.lu\/wp-content\/uploads\/sites\/4\/2026\/04\/24144328\/20200609-Belval-Campus_Henri-Goergen-23.jpg\",\"sameAs\":[\"https:\/\/www.facebook.com\/fstm.uni.lu\/\",\"https:\/\/www.linkedin.com\/showcase\/fstm-uni-lu\"],\"email\":\"communication@uni.lu\",\"telephone\":\"+3524666441\",\"address\":{\"@type\":\"PostalAddress\",\"streetAddress\":\"2, place de l\u2019Universit\u00e9\",\"addressLocality\":\"Esch-sur-Alzette\",\"postalCode\":\"4365\",\"addressCountry\":\"LU\"},\"description\":\"Faculty of Science, Technology and Medicine I Uni.lu\"}]}<\/script>\n<!-- \/ Yoast SEO Premium plugin. -->","yoast_head_json":{"title":"Physics Colloqium - FSTM events I Uni.lu","description":"The nonlinear response of quantum materials contains a wealth of information that is often hidden in the linear regime. Examples include second-harmonic","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.uni.lu\/fstm-en\/events\/physics-colloqium\/","og_locale":"en_GB","og_type":"article","og_title":"Physics Colloqium","og_description":"The nonlinear response of quantum materials contains a wealth of information that is often hidden in the linear regime. Examples include second-harmonic","og_url":"https:\/\/www.uni.lu\/fstm-en\/events\/physics-colloqium\/","og_site_name":"FSTM EN","article_publisher":"https:\/\/www.facebook.com\/fstm.uni.lu\/","article_modified_time":"2024-05-13T12:34:45+00:00","og_image":[{"width":792,"height":792,"url":"https:\/\/www.uni.lu\/wp-content\/uploads\/sites\/4\/2024\/02\/Peter_Orth.jpg","type":"image\/jpeg"}],"twitter_card":"summary_large_image","twitter_misc":{"Estimated reading time":"2 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/www.uni.lu\/fstm-en\/events\/physics-colloqium\/","url":"https:\/\/www.uni.lu\/fstm-en\/events\/physics-colloqium\/","name":"Physics Colloqium - FSTM events I Uni.lu","isPartOf":{"@id":"https:\/\/www.uni.lu\/fstm-en\/#website"},"primaryImageOfPage":{"@id":"https:\/\/www.uni.lu\/fstm-en\/events\/physics-colloqium\/#primaryimage"},"image":{"@id":"https:\/\/www.uni.lu\/fstm-en\/events\/physics-colloqium\/#primaryimage"},"thumbnailUrl":"https:\/\/www.uni.lu\/wp-content\/uploads\/sites\/4\/2024\/02\/Peter_Orth.jpg","datePublished":"2024-02-02T08:15:34+00:00","dateModified":"2024-05-13T12:34:45+00:00","description":"The nonlinear response of quantum materials contains a wealth of information that is often hidden in the linear regime. Examples include second-harmonic","breadcrumb":{"@id":"https:\/\/www.uni.lu\/fstm-en\/events\/physics-colloqium\/#breadcrumb"},"inLanguage":"en-GB","potentialAction":[{"@type":"ReadAction","target":["https:\/\/www.uni.lu\/fstm-en\/events\/physics-colloqium\/"]}]},{"@type":"ImageObject","inLanguage":"en-GB","@id":"https:\/\/www.uni.lu\/fstm-en\/events\/physics-colloqium\/#primaryimage","url":"https:\/\/www.uni.lu\/wp-content\/uploads\/sites\/4\/2024\/02\/Peter_Orth.jpg","contentUrl":"https:\/\/www.uni.lu\/wp-content\/uploads\/sites\/4\/2024\/02\/Peter_Orth.jpg","width":792,"height":792},{"@type":"BreadcrumbList","@id":"https:\/\/www.uni.lu\/fstm-en\/events\/physics-colloqium\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/www.uni.lu\/en"},{"@type":"ListItem","position":2,"name":"Faculty of Science, Technology and Medicine","item":"https:\/\/www.uni.lu\/fstm-en\/"},{"@type":"ListItem","position":3,"name":"Events","item":"https:\/\/www.uni.lu\/fstm-en\/events\/"},{"@type":"ListItem","position":4,"name":"Physics Colloqium"}]},{"@type":"WebSite","@id":"https:\/\/www.uni.lu\/fstm-en\/#website","url":"https:\/\/www.uni.lu\/fstm-en\/","name":"FSTM","description":"Faculty of Science, Technology and Medicine I Uni.lu","publisher":{"@id":"https:\/\/www.uni.lu\/fstm-en\/#organization"},"alternateName":"Faculty of Science, Technology and Medicine I University of Luxembourg","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/www.uni.lu\/fstm-en\/?s={search_term_string}"},"query-input":"required name=search_term_string"}],"inLanguage":"en-GB"},{"@type":"Organization","@id":"https:\/\/www.uni.lu\/fstm-en\/#organization","name":"FSTM - University of Luxembourg I Uni.lu","alternateName":"Faculty of Science, Technology and Medicine","url":"https:\/\/www.uni.lu\/fstm-en\/","logo":{"@type":"ImageObject","inLanguage":"en-GB","@id":"https:\/\/www.uni.lu\/fstm-en\/#\/schema\/logo\/image\/","url":"https:\/\/www.uni.lu\/wp-content\/uploads\/sites\/4\/2026\/03\/03111650\/FSTM_SM-Profile_1600x1600px-scaled.jpg","contentUrl":"https:\/\/www.uni.lu\/wp-content\/uploads\/sites\/4\/2026\/03\/03111650\/FSTM_SM-Profile_1600x1600px-scaled.jpg","width":2560,"height":2560,"caption":"FSTM - University of Luxembourg I Uni.lu"},"image":"https:\/\/www.uni.lu\/wp-content\/uploads\/sites\/4\/2026\/04\/24144328\/20200609-Belval-Campus_Henri-Goergen-23.jpg","sameAs":["https:\/\/www.facebook.com\/fstm.uni.lu\/","https:\/\/www.linkedin.com\/showcase\/fstm-uni-lu"],"email":"communication@uni.lu","telephone":"+3524666441","address":{"@type":"PostalAddress","streetAddress":"2, place de l\u2019Universit\u00e9","addressLocality":"Esch-sur-Alzette","postalCode":"4365","addressCountry":"LU"},"description":"Faculty of Science, Technology and Medicine I Uni.lu"}]}},"_links":{"self":[{"href":"https:\/\/www.uni.lu\/fstm-en\/wp-json\/wp\/v2\/events\/7854"}],"collection":[{"href":"https:\/\/www.uni.lu\/fstm-en\/wp-json\/wp\/v2\/events"}],"about":[{"href":"https:\/\/www.uni.lu\/fstm-en\/wp-json\/wp\/v2\/types\/events"}],"author":[{"embeddable":true,"href":"https:\/\/www.uni.lu\/fstm-en\/wp-json\/wp\/v2\/users\/52"}],"replies":[{"embeddable":true,"href":"https:\/\/www.uni.lu\/fstm-en\/wp-json\/wp\/v2\/comments?post=7854"}],"version-history":[{"count":4,"href":"https:\/\/www.uni.lu\/fstm-en\/wp-json\/wp\/v2\/events\/7854\/revisions"}],"predecessor-version":[{"id":13674,"href":"https:\/\/www.uni.lu\/fstm-en\/wp-json\/wp\/v2\/events\/7854\/revisions\/13674"}],"wp:authorship":[{"embeddable":true,"href":"https:\/\/www.uni.lu\/fstm-en\/wp-json\/wp\/v2\/users\/52"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.uni.lu\/fstm-en\/wp-json\/wp\/v2\/media\/7863"}],"wp:attachment":[{"href":"https:\/\/www.uni.lu\/fstm-en\/wp-json\/wp\/v2\/media?parent=7854"}],"wp:term":[{"taxonomy":"events-topic","embeddable":true,"href":"https:\/\/www.uni.lu\/fstm-en\/wp-json\/wp\/v2\/events-topic?post=7854"},{"taxonomy":"events-type","embeddable":true,"href":"https:\/\/www.uni.lu\/fstm-en\/wp-json\/wp\/v2\/events-type?post=7854"},{"taxonomy":"organisation","embeddable":true,"href":"https:\/\/www.uni.lu\/fstm-en\/wp-json\/wp\/v2\/organisation?post=7854"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}