{"285751":{"#nid":"285751","#data":{"type":"event","title":"Massless and Massive Electrons: Relativistic Physics in Condensed Matter Systems","body":[{"value":"\u003Ch5\u003ESchool of Physics Colloquium Series: Dr. Vidya Madhavan, Boston College\u003C\/h5\u003E\u003Cp\u003EElectrons in free space have a well-defined mass. Recently, a new class of materials called topological insulators were discovered, where the low energy electrons have\u0026nbsp;\u003Cem\u003Ezero\u003C\/em\u003E\u0026nbsp;mass. In fact, these electrons can be described by the same massless Dirac equation that is used to describe relativistic particles travelling close to the speed of light. In this talk I will describe our recent experimental and theoretical investigations of Topological Crystalline Insulators (TCIs) [1]. TCIs belong to the newest category of topological materials [2,3] where topology and crystal symmetry intertwine to create linearly dispersing Fermions similar to graphene. To study this material we use a scanning tunneling microscope. With the help of our high-resolution data, I will show how zero-mass electrons and massive electrons can coexist in the same material. I will discuss the conditions to obtain these zero mass electrons as well the method to impart a controllable mass to the particles and show how our studies create a path to engineering the Dirac band gap and realizing interaction-driven topological quantum phenomena in TCIs.\u003C\/p\u003E\u003Cp\u003E\u0026nbsp;[1]\u0026nbsp;\u0026nbsp;Y. Okada, et.al , Observation of Dirac node formation and mass acquisition in a topological crystalline insulator,\u0026nbsp;\u003Cem\u003EScience\u0026nbsp;\u003C\/em\u003E341\u003Cstrong\u003E\u003Cem\u003E,\u0026nbsp;\u003C\/em\u003E\u003C\/strong\u003E\u003Cem\u003E1496-1499\u0026nbsp;\u003C\/em\u003E(2013)\u003C\/p\u003E\u003Cp\u003E[2]\u0026nbsp;\u0026nbsp;L. Fu, Topological Crystalline Insulators.\u0026nbsp;\u003Cem\u003EPhys. Rev. Lett.\u0026nbsp;\u003C\/em\u003E106, 106802 (2011)\u003C\/p\u003E\u003Cp\u003E[3]\u0026nbsp;\u0026nbsp;T. H. Hsieh\u0026nbsp;\u003Cem\u003Eet al.\u003C\/em\u003E, Topological crystalline insulators in the SnTe material class.\u0026nbsp;\u003Cem\u003ENat.Commun.\u0026nbsp;\u003C\/em\u003E3, 982 (2012)\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":"","field_summary_sentence":[{"value":"Massless and Massive Electrons: Relativistic Physics in Condensed Matter Systems"}],"uid":"27664","created_gmt":"2014-03-26 10:29:43","changed_gmt":"2016-10-08 02:07:22","author":"Alison Morain","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2014-04-14T20:00:00-04:00","event_time_end":"2014-04-14T21:00:00-04:00","event_time_end_last":"2014-04-14T21:00:00-04:00","gmt_time_start":"2014-04-15 00:00:00","gmt_time_end":"2014-04-15 01:00:00","gmt_time_end_last":"2014-04-15 01:00:00","rrule":null,"timezone":"America\/New_York"},"extras":[],"groups":[{"id":"126011","name":"School of Physics"}],"categories":[],"keywords":[{"id":"89981","name":"Massless and Massive Electrons"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[{"id":"1795","name":"Seminar\/Lecture\/Colloquium"}],"invited_audience":[{"id":"78761","name":"Faculty\/Staff"}],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cp\u003E\u003Ca href=\u0022mailto:alison.morain@physics.gatech.edu\u0022\u003Ealison.morain@physics.gatech.edu\u003C\/a\u003E\u003C\/p\u003E","format":"limited_html"}],"email":[],"slides":[],"orientation":[],"userdata":""}}}