{"55557":{"#nid":"55557","#data":{"type":"news","title":"Seeing Moire in Graphene","body":[{"value":"\u003Cp\u003EResearchers at the Georgia Institute of Technology and the National Institute of Standards and Technology (NIST) have demonstrated that atomic scale moir\u00e9 patterns, an interference pattern that appears when two or more grids are overlaid slightly askew, can be used to measure how sheets of graphene are stacked and reveal areas of strain. The ability to determine the rotational orientation of graphene sheets and map strain is useful for understanding the electronic and transport properties of multiple layers of graphene, a one-atom thick form of carbon with potentially revolutionary semiconducting properties. The research appears in the journal, Physical Review B, in volume 81, issue 12.\u003Cbr \/\u003E\u003Cbr \/\u003EIn digital photography, moir\u00e9 (pronounced mwar-ray) patterns occur because of errors in the rendering process, which causes grid patterns to look wavy or distorted. Materials scientists have been using microscopic moir\u00e9 patterns to detect stresses such as wrinkles or bulges in a variety of materials.\u003Cbr \/\u003E\u003Cbr \/\u003EResearchers created graphene on the surface of a silicon carbide substrate at the Georgia Institute of Technology by heating one side so that only carbon, in the form of multilayer sheets of graphene, was left. Using a custom-built scanning tunneling microscope at NIST, the researchers were able to peer through the topmost layers of graphene to the layers beneath. This process, which the group dubbed \u0022atomic moir\u00e9 interferometry,\u0022 enabled them to image the patterns created by the stacked graphene layers, which in turn allowed the group to model how the hexagonal lattices of the individual graphene layers were stacked in relation to one another.\u003Cbr \/\u003E\u003Cbr \/\u003EUnlike other materials that tend to stretch out when they cool, graphene bunches up like a wrinkled bed sheet. The researchers were able to map these stress fields by comparing the relative distortion of the hexagons of carbon atoms that comprise the individual graphene layers. Their technique is so sensitive that it is able to detect strains in the graphene layers causing as little as a 0.1 percent change in atom spacing.\u003Cbr \/\u003E\u003Cbr \/\u003E\u201cThere\u2019s an ideal atomic lattice spacing in graphene. Knowing the strain distribution can help us in our efforts to create graphene with good electronic properties,\u201d said Phillip N. First, professor in the School of Physics at Georgia Tech. \u201cSo far, it looks as if multi-layered graphene has excellent conduction properties and may be useful for electronic applications.\u201d\u003Cbr \/\u003E\u003Cbr \/\u003EThis collaboration between Georgia Tech and NIST is part of a series of experiments aimed at gaining a fundamental understanding of the properties of graphene. Other examples of the group\u0027s work can been seen at \u003Ca href=\u0022http:\/\/www.mrs.org\/s_mrs\/bin.asp?CID=8684\u0026amp;DID=320520\u0026amp;DOC=FILE.PDF\u0022 title=\u0022www.mrs.org\/s_mrs\/bin.asp?CID=8684\u0026amp;DID=320520\u0026amp;DOC=FILE.PDF\u0022\u003Ewww.mrs.org\/s_mrs\/bin.asp?CID=8684\u0026amp;DID=320520\u0026amp;DOC=FILE.PDF\u003C\/a\u003E and \u003Ca href=\u0022http:\/\/www.mrs.org\/s_mrs\/bin.asp?CID=26616\u0026amp;DID=320529\u0026amp;DOC=FILE.PDF\u0022 title=\u0022www.mrs.org\/s_mrs\/bin.asp?CID=26616\u0026amp;DID=320529\u0026amp;DOC=FILE.PDF\u0022\u003Ewww.mrs.org\/s_mrs\/bin.asp?CID=26616\u0026amp;DID=320529\u0026amp;DOC=FILE.PDF\u003C\/a\u003E.\u003Cbr \/\u003E\u003Cbr \/\u003ETheir article, \u0022Structural analysis of multilayer graphene via atomic moir\u00e9 interferometry\u0022 was selected as an Editor\u0027s Highlight in Physical Review B for the month of March, 2010.\u003Cbr \/\u003E\u003Cbr \/\u003EWriters: Mark Esser and David Terraso\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003EResearchers at the Georgia Institute of Technology and the National Institute of Standards and Technology have demonstrated that atomic scale moir\u00e9 patterns, an interference pattern that appears when two or more grids are overlaid slightly askew, can be used to measure how sheets of graphene are stacked and reveal areas of strain. \u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"Researchers show how moire patterns can be used to meausure the strain of graphene sheets."}],"uid":"27310","created_gmt":"2010-05-05 08:55:51","changed_gmt":"2016-10-08 03:05:53","author":"David Terraso","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2010-05-05T00:00:00-04:00","iso_date":"2010-05-05T00:00:00-04:00","tz":"America\/New_York"},"extras":[],"hg_media":{"55558":{"id":"55558","type":"image","title":"Atomic Moire Pattern of Graphene","body":null,"created":"1449175533","gmt_created":"2015-12-03 20:45:33","changed":"1475894491","gmt_changed":"2016-10-08 02:41:31","alt":"Atomic Moire Pattern of Graphene","file":{"fid":"190314","name":"21977_web.jpg","image_path":"\/sites\/default\/files\/images\/21977_web_0.jpg","image_full_path":"http:\/\/www.tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/21977_web_0.jpg","mime":"image\/jpeg","size":73860,"path_740":"http:\/\/www.tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/21977_web_0.jpg?itok=Vc-GC1Je"}}},"media_ids":["55558"],"groups":[{"id":"1183","name":"Home"}],"categories":[{"id":"150","name":"Physics and Physical Sciences"}],"keywords":[{"id":"429","name":"graphene"},{"id":"9244","name":"moire"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cp\u003E\u003Cstrong\u003EGeorgia Tech Media Relations\u003C\/strong\u003E\u003Cbr \/\u003ELaura Diamond\u003Cbr \/\u003E\u003Ca href=\u0022mailto:laura.diamond@comm.gatech.edu\u0022\u003Elaura.diamond@comm.gatech.edu\u003C\/a\u003E\u003Cbr \/\u003E404-894-6016\u003Cbr \/\u003EJason Maderer\u003Cbr \/\u003E\u003Ca href=\u0022mailto:maderer@gatech.edu\u0022\u003Emaderer@gatech.edu\u003C\/a\u003E\u003Cbr \/\u003E404-660-2926\u003C\/p\u003E","format":"limited_html"}],"email":["david.terraso@comm.gatech.edu"],"slides":[],"orientation":[],"userdata":""}}}