{"274031":{"#nid":"274031","#data":{"type":"news","title":"Ballistic Transport in Graphene Suggests New Type of Electronic Device","body":[{"value":"\u003Cp\u003EUsing electrons more like photons could provide the foundation for a new type of electronic device that would capitalize on the ability of graphene to carry electrons with almost no resistance even at room temperature \u2013 a property known as ballistic transport.\u003C\/p\u003E\u003Cp\u003EResearch reported this week shows that electrical resistance in nanoribbons of epitaxial graphene changes in discrete steps following quantum mechanical principles. The research shows that the graphene nanoribbons act more like optical waveguides or quantum dots, allowing electrons to flow smoothly along the edges of the material. In ordinary conductors such as copper, resistance increases in proportion to the length as electrons encounter more and more impurities while moving through the conductor.\u003C\/p\u003E\u003Cp\u003EThe ballistic transport properties, similar to those observed in cylindrical carbon nanotubes, exceed theoretical conductance predictions for graphene by a factor of 10. The properties were measured in graphene nanoribbons approximately 40 nanometers wide that had been grown on the edges of three-dimensional structures etched into silicon carbide wafers.\u003C\/p\u003E\u003Cp\u003E\u201cThis work shows that we can control graphene electrons in very different ways because the properties are really exceptional,\u201d said \u003Ca href=\u0022https:\/\/www.physics.gatech.edu\/user\/walter-de-heer\u0022\u003EWalt de Heer\u003C\/a\u003E, a Regent\u2019s professor in the \u003Ca href=\u0022http:\/\/www.physics.gatech.edu\/\u0022\u003ESchool of Physics\u003C\/a\u003E at the Georgia Institute of Technology. \u201cThis could result in a new class of coherent electronic devices based on room temperature ballistic transport in graphene. Such devices would be very different from what we make today in silicon.\u201d\u003C\/p\u003E\u003Cp\u003EThe research, which was supported by the National Science Foundation, the Air Force Office of Scientific Research and the W.M. Keck Foundation, was reported February 5 in the journal \u003Cem\u003ENature\u003C\/em\u003E. The research was done through a collaboration of scientists from Georgia Tech in the United States, Leibniz Universit\u00e4t Hannover in Germany, the Centre National de la Recherche Scientifique (CNRS) in France and Oak Ridge National Laboratory \u2013 supported by the Department of Energy \u2013 in the United States.\u003C\/p\u003E\u003Cp\u003EFor nearly a decade, researchers have been trying to use the unique properties of graphene to create electronic devices that operate much like existing silicon semiconductor chips. But those efforts have met with limited success because graphene \u2013 a lattice of carbon atoms that can be made as little as one layer thick \u2013 cannot be easily given the electronic bandgap that such devices need to operate.\u003C\/p\u003E\u003Cp\u003EDe Heer argues that researchers should stop trying to use graphene like silicon, and instead use its unique electron transport properties to design new types of electronic devices that could allow ultra-fast computing \u2013 based on a new approach to switching. Electrons in the graphene nanoribbons can move tens or hundreds of microns without scattering.\u003C\/p\u003E\u003Cp\u003E\u201cThis constant resistance is related to one of the fundamental constants of physics, the conductance quantum,\u201d de Heer said. \u201cThe resistance of this channel does not depend on temperature, and it does not depend on the amount of current you are putting through it.\u201d\u003C\/p\u003E\u003Cp\u003EWhat does disrupt the flow of electrons, however, is measuring the resistance with an electrical probe. The measurements showed that touching the nanoribbons with a single probe doubles the resistance; touching it with two probes triples the resistance.\u003C\/p\u003E\u003Cp\u003E\u201cThe electrons hit the probe and scatter,\u201d explained de Heer. \u201cIt\u2019s a lot like a stream in which water is flowing nicely until you put rocks in the way. We have done systematic studies to show that when you touch the nanoribbons with a probe, you introduce a method for the electrons to scatter, and that changes the resistance.\u201d\u003C\/p\u003E\u003Cp\u003EThe nanoribbons are grown epitaxially on silicon carbon wafers into which patterns have been etched using standard microelectronics fabrication techniques. When the wafers are heated to approximately 1,000 degrees Celsius, silicon is preferentially driven off along the edges, forming graphene nanoribbons whose structure is determined by the pattern of the three-dimensional surface. Once grown, the nanoribbons require no further processing.\u003C\/p\u003E\u003Cp\u003EThe advantage of fabricating graphene nanoribbons this way is that it produces edges that are perfectly smooth, annealed by the fabrication process. The smooth edges allow electrons to flow through the nanoribbons without disruption. If traditional etching techniques are used to cut nanoribbons from graphene sheets, the resulting edges are too rough to allow ballistic transport.\u003C\/p\u003E\u003Cp\u003E\u201cIt seems that the current is primarily flowing on the edges,\u201d de Heer said. \u201cThere are other electrons in the bulk portion of the nanoribbons, but they do not interact with the electrons flowing at the edges.\u201d\u003C\/p\u003E\u003Cp\u003EThe electrons on the edge flow more like photons in optical fiber, helping them avoid scattering. \u201cThese electrons are really behaving more like light,\u201d he said. \u201cIt is like light going through an optical fiber. Because of the way the fiber is made, the light transmits without scattering.\u201d\u003C\/p\u003E\u003Cp\u003EThe researchers measured ballistic conductance in the graphene nanoribbons for up to 16 microns. Electron mobility measurements surpassing one million correspond to a sheet resistance of one ohm per square that is two orders of magnitude lower than what is observed in two-dimensional graphene \u2013 and ten times smaller than the best theoretical predictions for graphene.\u003C\/p\u003E\u003Cp\u003E\u201cThis should enable a new way of doing electronics,\u201d de Heer said. \u201cWe are already able to steer these electrons and we can switch them using rudimentary means. We can put a roadblock, and then open it up again. New kinds of switches for this material are now on the horizon.\u201d\u003C\/p\u003E\u003Cp\u003ETheoretical explanations for what the researchers have measured are incomplete. De Heer speculates that the graphene nanoribbons may be producing a new type of electronic transport similar to what is observed in superconductors. \u0026nbsp;\u003C\/p\u003E\u003Cp\u003E\u201cThere is a lot of fundamental physics that needs to be done to understand what we are seeing,\u201d he added. \u201cWe believe this shows that there is a real possibility for a new type of graphene-based electronics.\u201d\u003C\/p\u003E\u003Cp\u003EGeorgia Tech researchers have pioneered graphene-based electronics since 2001, for which they hold a patent, filed in 2003. The technique involves etching patterns into electronics-grade silicon carbide wafers, then heating the wafers to drive off silicon, leaving patterns of graphene.\u003C\/p\u003E\u003Cp\u003EIn addition to de Heer, the paper\u2019s authors included Jens Baringhaus, Frederik Edler and Christoph Tegenkamp from the Institut f\u00fcr Festk\u00f6rperphysik, Leibniz Universit\u00e4t, Hannover in Germany; Edward Conrad, Ming Ruan and Zhigang Jiang from the School of Physics at Georgia Tech; Claire Berger from Georgia Tech and Institut N\u00e9el at the Centre National de la Recherche Scientifique (CNRS) in France; Antonio Tejeda and Muriel Sicot from the Institut Jean Lamour, Universite de Nancy, Centre National de la Recherche Scientifique (CNRS) in France; An-Ping Li from the Center for Nanophase Materials Sciences at Oak Ridge National Laboratory, and Amina Taleb-Ibrahimi from the CNRS Synchotron SOLEIL in France.\u003C\/p\u003E\u003Cp\u003EThis research was supported by the National Science Foundation (NSF) Materials Research Science and Engineering Center (MRSEC) at Georgia Tech through award DMR-0820382; the Air Force Office of Scientific Research (AFOSR); the Scientific User Facilities Division, Office of Basic Energy Sciences, U.S. Department of Energy, and the Partner University Fund from the Embassy of France. Any conclusions or recommendations are those of the authors and do not necessarily represent the official views of the NSF, DOE or AFOSR.\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003ECITATION\u003C\/strong\u003E: Jens Baringhaus, et al., \u201cExceptional ballistic transport in epitaxial graphene nanoribbons,\u201d (Nature 2013). (\u003Ca href=\u0022http:\/\/dx.doi.org\/10.1038\/nature12952\u0022\u003Ehttp:\/\/dx.doi.org\/10.1038\/nature12952\u003C\/a\u003E).\u003Cbr \/\u003E\u003Cbr \/\u003E\u003Cstrong\u003EResearch News\u003C\/strong\u003E\u003Cbr \/\u003E\u003Cstrong\u003EGeorgia Institute of Technology\u003C\/strong\u003E\u003Cbr \/\u003E\u003Cstrong\u003E177 North Avenue\u003C\/strong\u003E\u003Cbr \/\u003E\u003Cstrong\u003EAtlanta, Georgia\u0026nbsp; 30332-0181\u0026nbsp; USA\u003C\/strong\u003E\u003Cbr \/\u003E\u003Cbr \/\u003E\u003Cstrong\u003EMedia Relations Contacts\u003C\/strong\u003E: John Toon (404-894-6986) (\u003Ca href=\u0022mailto:jtoon@gatech.edu\u0022\u003Ejtoon@gatech.edu\u003C\/a\u003E) or Brett Israel (404-385-1933) (\u003Ca href=\u0022mailto:brett.israel@comm.gatech.edu\u0022\u003Ebrett.israel@comm.gatech.edu\u003C\/a\u003E).\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EWriter\u003C\/strong\u003E: John Toon\u003Cbr \/\u003E\u003Cbr \/\u003E\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003EUsing electrons more like photons could provide the foundation for a new type of electronic device that would capitalize on the ability of graphene to carry electrons with almost no resistance even at room temperature \u2013 a property known as ballistic transport.\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"Using electrons more like photons could provide the foundation for a new type of electronic device that would capitalize on the ability of graphene to carry electrons with almost no resistance."}],"uid":"27303","created_gmt":"2014-02-05 11:38:02","changed_gmt":"2016-10-08 03:15:51","author":"John Toon","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2014-02-05T00:00:00-05:00","iso_date":"2014-02-05T00:00:00-05:00","tz":"America\/New_York"},"extras":[],"hg_media":{"274011":{"id":"274011","type":"image","title":"Ballistic Transport in Graphene Nanoribbons","body":null,"created":"1449244112","gmt_created":"2015-12-04 15:48:32","changed":"1475894964","gmt_changed":"2016-10-08 02:49:24","alt":"Ballistic Transport in Graphene Nanoribbons","file":{"fid":"198711","name":"graphene-nanoribbons.jpg","image_path":"\/sites\/default\/files\/images\/graphene-nanoribbons_0.jpg","image_full_path":"http:\/\/www.tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/graphene-nanoribbons_0.jpg","mime":"image\/jpeg","size":1120437,"path_740":"http:\/\/www.tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/graphene-nanoribbons_0.jpg?itok=-qqd5pwt"}},"274001":{"id":"274001","type":"image","title":"Walt de Heer - Ballistic Transport","body":null,"created":"1449244112","gmt_created":"2015-12-04 15:48:32","changed":"1475894964","gmt_changed":"2016-10-08 02:49:24","alt":"Walt de Heer - Ballistic Transport","file":{"fid":"198710","name":"walt-de-heer.jpg","image_path":"\/sites\/default\/files\/images\/walt-de-heer_0.jpg","image_full_path":"http:\/\/www.tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/walt-de-heer_0.jpg","mime":"image\/jpeg","size":947684,"path_740":"http:\/\/www.tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/walt-de-heer_0.jpg?itok=IEGnB69-"}}},"media_ids":["274011","274001"],"groups":[{"id":"1188","name":"Research Horizons"}],"categories":[{"id":"145","name":"Engineering"},{"id":"149","name":"Nanotechnology and Nanoscience"},{"id":"135","name":"Research"},{"id":"150","name":"Physics and Physical Sciences"}],"keywords":[{"id":"85841","name":"ballistic transport"},{"id":"9116","name":"epitaxial graphene"},{"id":"429","name":"graphene"},{"id":"12423","name":"nanoribbons"},{"id":"166937","name":"School of Physics"},{"id":"12422","name":"Walt de Heer"}],"core_research_areas":[{"id":"39451","name":"Electronics and Nanotechnology"},{"id":"39471","name":"Materials"}],"news_room_topics":[{"id":"71881","name":"Science and Technology"}],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cp\u003EJohn Toon\u003C\/p\u003E\u003Cp\u003EResearch News\u003C\/p\u003E\u003Cp\u003E\u003Ca href=\u0022mailto:jtoon@gatech.edu\u0022\u003Ejtoon@gatech.edu\u003C\/a\u003E\u003C\/p\u003E\u003Cp\u003E(404) 894-6986\u003C\/p\u003E","format":"limited_html"}],"email":["jtoon@gatech.edu"],"slides":[],"orientation":[],"userdata":""}},"255471":{"#nid":"255471","#data":{"type":"news","title":"Chemically Engineered Graphene-Based 2D Organic Molecular Magnet","body":[{"value":"\u003Cp\u003ECarbon-based magnetic materials and structures of mesoscopic dimensions may offer unique opportunities for future nanomagnetoelectronic\/spintronic devices. To achieve their potential, carbon nanosystems must have controllable magnetic properties. We demonstrate that nitrophenyl functionalized graphene can act as a room-temperature 2D magnet. We report a comprehensive study of low-temperature magnetotransport, vibrating sample magnetometry (VSM), and superconducting quantum interference (SQUID) measurements before and after radical functionalization. Following nitrophenyl (NP) functionalization, epitaxially grown graphene systems can become organic molecular magnets with ferromagnetic and antiferromagnetic ordering that persists at temperatures above 400 K. The field-dependent, surface magnetoelectric properties were studied using scanning probe microscopy (SPM) techniques. The results indicate that the NP-functionalization orientation and degree of coverage directly affect the magnetic properties of the graphene surface. In addition, graphene-based organic magnetic nanostructures were found to demonstrate a pronounced magneto-optical Kerr effect (MOKE). The results were consistent across different characterization techniques and indicate room-temperature magnetic ordering along preferred graphene orientations in the NP-functionalized samples. Chemically isolated graphene nanoribbons (CINs) were observed along the preferred functionality directions. These results pave the way for future magnetoelectronic\/spintronic applications based on promising concepts such as current-induced magnetization switching, magnetoelectricity, half-metallicity, and quantum tunneling of magnetization.\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003ECarbon-based magnetic materials and structures of mesoscopic dimensions may offer unique opportunities for future nanomagnetoelectronic\/spintronic devices. To achieve their potential, carbon nanosystems must have controllable magnetic properties. We demonstrate that nitrophenyl functionalized graphene can act as a room-temperature 2D magnet. We report a comprehensive study of low-temperature magnetotransport, vibrating sample magnetometry (VSM), and superconducting quantum interference (SQUID) measurements before and after radical functionalization.\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"We demonstrate that nitrophenyl functionalized graphene can act as a room-temperature 2D magnet."}],"uid":"27428","created_gmt":"2013-11-15 16:50:34","changed_gmt":"2016-10-08 03:15:22","author":"Gina Adams","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2013-10-25T00:00:00-04:00","iso_date":"2013-10-25T00:00:00-04:00","tz":"America\/New_York"},"extras":[],"hg_media":{"256571":{"id":"256571","type":"image","title":"Figure 1","body":null,"created":"1449243846","gmt_created":"2015-12-04 15:44:06","changed":"1475894936","gmt_changed":"2016-10-08 02:48:56","alt":"Figure 1","file":{"fid":"198227","name":"figure1_0.jpeg","image_path":"\/sites\/default\/files\/images\/figure1_0_0.jpeg","image_full_path":"http:\/\/www.tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/figure1_0_0.jpeg","mime":"image\/jpeg","size":586298,"path_740":"http:\/\/www.tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/figure1_0_0.jpeg?itok=BJD6R9mN"}}},"media_ids":["256571"],"related_links":[{"url":"http:\/\/pubs.acs.org\/doi\/abs\/10.1021\/nn403939r","title":"ACS Nano"}],"groups":[{"id":"60783","name":"MRSEC"}],"categories":[{"id":"42941","name":"Art Research"}],"keywords":[{"id":"9116","name":"epitaxial graphene"}],"core_research_areas":[{"id":"39451","name":"Electronics and Nanotechnology"},{"id":"39471","name":"Materials"}],"news_room_topics":[],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}},"255461":{"#nid":"255461","#data":{"type":"news","title":"Exceptional ballistic transport in epitaxial graphene nanoribbons","body":[{"value":"\u003Cp\u003EAuthors:\u0026nbsp; \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Baringhaus_J\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EJens Baringhaus\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Ruan_M\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EMing Ruan\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Edler_F\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EFrederik Edler\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Tejeda_A\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EAntonio Tejeda\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Sicot_M\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EMuriel Sicot\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Ibrahimi_A\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EAmina Taleb Ibrahimi\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Jiang_Z\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EZhigang Jiang\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Conrad_E\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EEdward Conrad\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Berger_C\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EClaire Berger\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Tegenkamp_C\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EChristoph Tegenkamp\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Heer_W\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EWalt A.de Heer\u003C\/a\u003E\u003C\/p\u003E\u003Cp\u003EGraphene electronics has motivated much of graphene science for the past decade. A primary goal was to develop high mobility semiconducting graphene with a band gap that is large enough for high performance applications. Graphene ribbons were thought to be semiconductors with these properties, however efforts to produce ribbons with useful bandgaps and high mobility has had limited success. We show here that high quality epitaxial graphene nanoribbons 40 nm in width, with annealed edges, grown on sidewall SiC are not semiconductors, but single channel room temperature ballistic conductors for lengths up to at least 16 micrometers. Mobilities exceeding one million corresponding to a sheet resistance below 1 Ohm have been observed, thereby surpassing two dimensional graphene by 3 orders of magnitude and theoretical predictions for perfect graphene by more than a factor of 10. The graphene ribbons behave as electronic waveguides or quantum dots. We show that transport in these ribbons is dominated by two components of the ground state transverse waveguide mode, one that is ballistic and temperature independent, and a second thermally activated component that appears to be ballistic at room temperature and insulating at cryogenic temperatures. At room temperature the resistance of both components abruptly increases with increasing length, one at a length of 160 nm and the other at 16 micrometers. These properties appear to be related to the lowest energy quantum states in the charge neutral ribbons. Since epitaxial graphene nanoribbons are readily produced by the thousands, their room temperature ballistic transport properties can be used in advanced nanoelectronics as well.\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003EGraphene electronics has motivated much of graphene science for the past decade. A primary goal was to develop high mobility semiconducting graphene with a band gap that is large enough for high performance applications. Graphene ribbons were thought to be semiconductors with these properties, however efforts to produce ribbons with useful bandgaps and high mobility has had limited success. We show here that high quality epitaxial graphene nanoribbons 40 nm in width, with annealed edges, grown on sidewall SiC are not semiconductors, but single channel room temperature ballistic conductors for lengths up to at least 16 micrometers.\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"We show here that high quality epitaxial graphene nanoribbons 40 nm in width, with annealed edges, grown on sidewall SiC are not semiconductors, but single channel room temperature ballistic conductors for lengths up to at least 16 micrometers."}],"uid":"27428","created_gmt":"2013-11-15 16:46:09","changed_gmt":"2016-10-08 03:15:22","author":"Gina Adams","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2013-08-26T00:00:00-04:00","iso_date":"2013-08-26T00:00:00-04:00","tz":"America\/New_York"},"extras":[],"hg_media":{"257311":{"id":"257311","type":"image","title":"A. Surface characterization: ARPES and STM","body":null,"created":"1449243856","gmt_created":"2015-12-04 15:44:16","changed":"1475894938","gmt_changed":"2016-10-08 02:48:58","alt":"A. Surface characterization: ARPES and STM","file":{"fid":"198249","name":"article2.jpg","image_path":"\/sites\/default\/files\/images\/article2_0.jpg","image_full_path":"http:\/\/www.tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/article2_0.jpg","mime":"image\/jpeg","size":91374,"path_740":"http:\/\/www.tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/article2_0.jpg?itok=LnULdTLX"}}},"media_ids":["257311"],"related_links":[{"url":"http:\/\/arxiv.org\/abs\/1301.5354","title":"http:\/\/arxiv.org\/abs\/1301.5354"}],"groups":[{"id":"60783","name":"MRSEC"}],"categories":[{"id":"42941","name":"Art Research"}],"keywords":[{"id":"9116","name":"epitaxial graphene"}],"core_research_areas":[{"id":"39451","name":"Electronics and Nanotechnology"},{"id":"39471","name":"Materials"}],"news_room_topics":[],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}},"255441":{"#nid":"255441","#data":{"type":"news","title":"Wafer bonding solution to epitaxial graphene \u2013 silicon integration","body":[{"value":"\u003Cp\u003EAuthors:\u0026nbsp; \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Dong_R\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003ERui Dong\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Guo_Z\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EZelei Guo\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Palmer_J\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EJames Palmer\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Hu_Y\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EYike Hu\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Ruan_M\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EMing Ruan\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Hankinson_J\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EJohn Hankinson\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Kunc_J\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EJan Kunc\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Bhattacharya_S\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003ESwapan K Bhattacharya\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Berger_C\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EClaire Berger\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Heer_W\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EWalt A. de Heer\u003C\/a\u003E\u003C\/p\u003E\u003Cp\u003EThe development of graphene electronics requires the integration of graphene devices with Si-CMOS technology. Most strategies involve the transfer of graphene sheets onto silicon, with the inherent difficulties of clean transfer and subsequent graphene nano-patterning that degrades considerably the electronic mobility of nanopatterned graphene. Epitaxial graphene (EG) by contrast is grown on an essentially perfect crystalline (semi-insulating) surface, and graphene nanostructures with exceptional properties have been realized by a selective growth process on tailored SiC surface that requires no graphene patterning. However, the temperatures required in this structured growth process are too high for silicon technology. Here we demonstrate a new graphene to Si integration strategy, with a bonded and interconnected compact double-wafer structure. Using silicon-on-insulator technology (SOI) a thin monocrystalline silicon layer ready for CMOS processing is applied on top of epitaxial graphene on SiC. The parallel Si and graphene platforms are interconnected by metal vias. This method inspired by the industrial development of 3d hyper-integration stacking thin-film electronic devices preserves the advantages of epitaxial graphene and enables the full spectrum of CMOS processing.\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003EThe development of graphene electronics requires the integration of graphene devices with Si-CMOS technology. Most strategies involve the transfer of graphene sheets onto silicon, with the inherent difficulties of clean transfer and subsequent graphene nano-patterning that degrades considerably the electronic mobility of nanopatterned graphene.\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"Here we demonstrate a new graphene to Si integration strategy, with a bonded and interconnected compact double-wafer structure."}],"uid":"27428","created_gmt":"2013-11-15 16:28:18","changed_gmt":"2016-10-08 03:15:22","author":"Gina Adams","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2013-08-13T00:00:00-04:00","iso_date":"2013-08-13T00:00:00-04:00","tz":"America\/New_York"},"extras":[],"hg_media":{"257331":{"id":"257331","type":"image","title":"Wafer bonding solution to epitaxial graphene \u2013 silicon integration Figure 1","body":null,"created":"1449243856","gmt_created":"2015-12-04 15:44:16","changed":"1475894938","gmt_changed":"2016-10-08 02:48:58","alt":"Wafer bonding solution to epitaxial graphene \u2013 silicon integration Figure 1","file":{"fid":"198250","name":"article3.jpg","image_path":"\/sites\/default\/files\/images\/article3_0.jpg","image_full_path":"http:\/\/www.tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/article3_0.jpg","mime":"image\/jpeg","size":114707,"path_740":"http:\/\/www.tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/article3_0.jpg?itok=4np3S_ST"}}},"media_ids":["257331"],"related_links":[{"url":"http:\/\/arxiv.org\/abs\/1308.2697","title":"http:\/\/arxiv.org\/abs\/1308.2697"}],"groups":[{"id":"60783","name":"MRSEC"}],"categories":[{"id":"42931","name":"Performances"}],"keywords":[{"id":"9116","name":"epitaxial graphene"}],"core_research_areas":[{"id":"39451","name":"Electronics and Nanotechnology"},{"id":"39471","name":"Materials"}],"news_room_topics":[],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}},"255431":{"#nid":"255431","#data":{"type":"news","title":"Probing terahertz surface plasmon waves in graphene structures","body":[{"value":"\u003Cp\u003EAuthors:\u0026nbsp; \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Mitrofanov_O\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EOleg Mitrofanov\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Yu_W\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EWenlong Yu\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Thompson_R\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003ERobert J. Thompson\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Jiang_Y\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EYuxuan Jiang\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Brener_I\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EIgal Brener\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Pan_W\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EWei Pan\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Berger_C\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EClaire Berger\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Heer_W\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EWalter A. de Heer\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Jiang_Z\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EZhigang Jiang\u003C\/a\u003E\u003C\/p\u003E\u003Cp\u003EEpitaxial graphene mesas and ribbons are investigated using terahertz (THz) nearfield microscopy to probe surface plasmon excitation and THz transmission properties on the sub-wavelength scale. The THz near-field images show variation of graphene properties on a scale smaller than the wavelength, and excitation of THz surface waves occurring at graphene edges, similar to that observed at metallic edges. The Fresnel reflection at the substrate SiC\/air interface is also found to be altered by the presence of graphene ribbon arrays, leading to either reduced or enhanced transmission of the THz wave depending on the wave polarization and the ribbon width.\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003EEpitaxial graphene mesas and ribbons are investigated using terahertz (THz) nearfield microscopy to probe surface plasmon excitation and THz transmission properties on the sub-wavelength scale. The THz near-field images show variation of graphene properties on a scale smaller than the wavelength, and excitation of THz surface waves occurring at graphene edges, similar to that observed at metallic edges.\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"Epitaxial graphene mesas and ribbons are investigated using terahertz (THz) nearfield microscopy to probe surface plasmon excitation and THz transmission properties on the sub-wavelength scale."}],"uid":"27428","created_gmt":"2013-11-15 16:18:29","changed_gmt":"2016-10-08 03:15:22","author":"Gina Adams","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2013-07-29T00:00:00-04:00","iso_date":"2013-07-29T00:00:00-04:00","tz":"America\/New_York"},"extras":[],"hg_media":{"257341":{"id":"257341","type":"image","title":"Probing terahertz surface plasmon waves in graphene structures","body":null,"created":"1449243856","gmt_created":"2015-12-04 15:44:16","changed":"1475894938","gmt_changed":"2016-10-08 02:48:58","alt":"Probing terahertz surface plasmon waves in graphene structures","file":{"fid":"198251","name":"article4.jpg","image_path":"\/sites\/default\/files\/images\/article4_0.jpg","image_full_path":"http:\/\/www.tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/article4_0.jpg","mime":"image\/jpeg","size":57480,"path_740":"http:\/\/www.tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/article4_0.jpg?itok=XPrVhQrc"}}},"media_ids":["257341"],"related_links":[{"url":"http:\/\/arxiv.org\/abs\/1307.7374","title":"http:\/\/arxiv.org\/abs\/1307.7374"}],"groups":[{"id":"60783","name":"MRSEC"}],"categories":[{"id":"42941","name":"Art Research"}],"keywords":[{"id":"9116","name":"epitaxial graphene"}],"core_research_areas":[{"id":"39451","name":"Electronics and Nanotechnology"},{"id":"39471","name":"Materials"}],"news_room_topics":[],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}},"255281":{"#nid":"255281","#data":{"type":"news","title":"Local tuning of graphene thickness on 4H-SiC C-face using decomposing silicon nitride masks","body":[{"value":"\u003Cp\u003EAuthors:\u0026nbsp; \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Puybaret_R\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003ERenaud Puybaret\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Hankinson_J\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EJohn Hankinson\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Ougazzaden_A\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EAbdallah Ougazzaden\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Voss_P\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EPaul L Voss\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Berger_C\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EClaire Berger\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Heer_W\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EWalt A de Heer\u003C\/a\u003E\u003C\/p\u003E\u003Cp\u003EPatterning of graphene is key for device fabrication. We report a way to increase or reduce the number of layers in epitaxial graphene grown on the C-face (000-1) of silicon carbide by the deposition of a 120 nm to 150nm-thick silicon nitride mask prior to graphitization. In our process we find that areas covered by a Si-rich SiN mask have three more layers than non-masked areas. Conversely N-rich SiN decreases the thickness by three layers. In both cases the mask decomposes before graphitization is completed. Graphene grown in masked areas show good quality as observed by Raman, AFM and transport data. By tailoring the growth parameters selective graphene growth has been obtained.\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003EPatterning of graphene is key for device fabrication. We report a way to increase or reduce the number of layers in epitaxial graphene grown on the C-face (000-1) of silicon carbide by the deposition of a 120 nm to 150nm-thick silicon nitride mask prior to graphitization.\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"We report a way to increase or reduce the number of layers in epitaxial graphene grown on the C-face (000-1) of silicon carbide by the deposition of a 120 nm to 150nm-thick silicon nitride mask prior to graphitization."}],"uid":"27428","created_gmt":"2013-11-15 15:23:13","changed_gmt":"2016-10-08 03:15:22","author":"Gina Adams","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2013-07-23T00:00:00-04:00","iso_date":"2013-07-23T00:00:00-04:00","tz":"America\/New_York"},"extras":[],"hg_media":{"257351":{"id":"257351","type":"image","title":"Local tuning of graphene thickness on 4H-SiC C-face using decomposing silicon nitride masks","body":null,"created":"1449243856","gmt_created":"2015-12-04 15:44:16","changed":"1475894938","gmt_changed":"2016-10-08 02:48:58","alt":"Local tuning of graphene thickness on 4H-SiC C-face using decomposing silicon nitride masks","file":{"fid":"198252","name":"article5.jpg","image_path":"\/sites\/default\/files\/images\/article5_0.jpg","image_full_path":"http:\/\/www.tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/article5_0.jpg","mime":"image\/jpeg","size":54825,"path_740":"http:\/\/www.tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/article5_0.jpg?itok=pffFm8V8"}}},"media_ids":["257351"],"related_links":[{"url":"http:\/\/arxiv.org\/abs\/1307.6197","title":"http:\/\/arxiv.org\/abs\/1307.6197"}],"groups":[{"id":"60783","name":"MRSEC"}],"categories":[{"id":"42941","name":"Art Research"}],"keywords":[{"id":"429","name":"graphene"}],"core_research_areas":[{"id":"39451","name":"Electronics and Nanotechnology"},{"id":"39471","name":"Materials"}],"news_room_topics":[],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}},"255261":{"#nid":"255261","#data":{"type":"news","title":"Highly efficient spin transport in epitaxial graphene on SiC","body":[{"value":"\u003Cp\u003EAuthors:\u0026nbsp; \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Dlubak_B\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EBruno Dlubak\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Martin_M\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EMarie-Blandine Martin\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Deranlot_C\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003ECyrile Deranlot\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Servet_B\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EBernard Servet\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Xavier_S\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003ESt\u00e9phane Xavier\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Mattana_R\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003ERichard Mattana\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Sprinkle_M\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EMike Sprinkle\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Berger_C\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EClaire Berger\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Heer_W\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EWalt A. De Heer\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Petroff_F\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EFr\u00e9d\u00e9ric Petroff\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Anane_A\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EAbdelmadjid Anane\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Seneor_P\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EPierre Seneor\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Fert_A\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EAlbert Fert\u003C\/a\u003E\u003C\/p\u003E\u003Cp\u003ESpin information processing is a possible new paradigm for post-CMOS (complementary metal-oxide semiconductor) electronics and efficient spin propagation over long distances is fundamental to this vision. However, despite several decades of intense research, a suitable platform is still wanting. We report here on highly efficient spin transport in two-terminal polarizer\/analyser devices based on high-mobility epitaxial graphene grown on silicon carbide. Taking advantage of high-impedance injecting\/detecting tunnel junctions, we show spin transport efficiencies up to 75%, spin signals in the mega-ohm range and spin diffusion lengths exceeding 100 {\\mu}m. This enables spintronics in complex structures: devices and network architectures relying on spin information processing, well beyond present spintronics applications, can now be foreseen.\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003ESpin information processing is a possible new paradigm for post-CMOS (complementary metal-oxide semiconductor) electronics and efficient spin propagation over long distances is fundamental to this vision. However, despite several decades of intense research, a suitable platform is still wanting. We report here on highly efficient spin transport in two-terminal polarizer\/analyser devices based on high-mobility epitaxial graphene grown on silicon carbide.\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"We report here on highly efficient spin transport in two-terminal polarizer\/analyser devices based on high-mobility epitaxial graphene grown on silicon carbide"}],"uid":"27428","created_gmt":"2013-11-15 15:19:56","changed_gmt":"2016-10-08 03:15:22","author":"Gina Adams","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2013-07-07T00:00:00-04:00","iso_date":"2013-07-07T00:00:00-04:00","tz":"America\/New_York"},"extras":[],"hg_media":{"257361":{"id":"257361","type":"image","title":"Highly ef\ufb01cient spin transport in epitaxial graphene on SiC","body":null,"created":"1449243856","gmt_created":"2015-12-04 15:44:16","changed":"1475894938","gmt_changed":"2016-10-08 02:48:58","alt":"Highly ef\ufb01cient spin transport in epitaxial graphene on SiC","file":{"fid":"198253","name":"article6.jpg","image_path":"\/sites\/default\/files\/images\/article6_0.jpg","image_full_path":"http:\/\/www.tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/article6_0.jpg","mime":"image\/jpeg","size":87864,"path_740":"http:\/\/www.tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/article6_0.jpg?itok=i33-bg4Y"}}},"media_ids":["257361"],"related_links":[{"url":"http:\/\/arxiv.org\/abs\/1307.1555","title":"http:\/\/arxiv.org\/abs\/1307.1555"}],"groups":[{"id":"60783","name":"MRSEC"}],"categories":[{"id":"42941","name":"Art Research"}],"keywords":[{"id":"9116","name":"epitaxial graphene"}],"core_research_areas":[{"id":"39451","name":"Electronics and Nanotechnology"},{"id":"39471","name":"Materials"}],"news_room_topics":[],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}},"255241":{"#nid":"255241","#data":{"type":"news","title":"A method to extract pure Raman spectrum of epitaxial graphene on SiC","body":[{"value":"\u003Cp\u003EAuthors:\u0026nbsp; \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Kunc_J\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EJan Kunc\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Hu_Y\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EYike Hu\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Palmer_J\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EJames Palmer\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Berger_C\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EClaire Berger\u003C\/a\u003E, \u003Ca href=\u0022http:\/\/arxiv.org\/find\/cond-mat\/1\/au:+Heer_W\/0\/1\/0\/all\/0\/1\u0022 rel=\u0022nofollow\u0022\u003EWalter A. de Heer\u003C\/a\u003E\u003C\/p\u003E\u003Cp\u003EA method is proposed to extract pure Raman spectrum of epitaxial graphene on SiC by using a Non-negative Matrix Factorization. It overcomes problems of negative spectral intensity and poorly resolved spectra resulting from a simple subtraction of a SiC background from the experimental data. We also show that the method is similar to deconvolution, for spectra composed of multiple sub- micrometer areas, with the advantage that no prior information on the impulse response functions is needed. We have used this property to characterize the Raman laser beam. The method capability in efficient data smoothing is also demonstrated\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003EA method is proposed to extract pure Raman spectrum of epitaxial graphene on SiC by using a Non-negative Matrix Factorization. It overcomes problems of negative spectral intensity and poorly resolved spectra resulting from a simple subtraction of a SiC background from the experimental data. We also show that the method is similar to deconvolution, for spectra composed of multiple sub- micrometer areas, with the advantage that no prior information on the impulse response functions is needed. We have used this property to characterize the Raman laser beam. The method capability in efficient data smoothing is also demonstrated\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"A method is proposed to extract pure Raman spectrum of epitaxial graphene on SiC by using a Non-negative Matrix Factorization"}],"uid":"27428","created_gmt":"2013-11-15 15:12:57","changed_gmt":"2016-10-08 03:15:22","author":"Gina Adams","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2013-07-01T00:00:00-04:00","iso_date":"2013-07-01T00:00:00-04:00","tz":"America\/New_York"},"extras":[],"hg_media":{"257371":{"id":"257371","type":"image","title":"A method to extract pure Raman spectrum of epitaxial graphene on SiC","body":null,"created":"1449243856","gmt_created":"2015-12-04 15:44:16","changed":"1475894938","gmt_changed":"2016-10-08 02:48:58","alt":"A method to extract pure Raman spectrum of epitaxial graphene on SiC","file":{"fid":"198254","name":"2_4.jpg","image_path":"\/sites\/default\/files\/images\/2_4_0.jpg","image_full_path":"http:\/\/www.tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/2_4_0.jpg","mime":"image\/jpeg","size":598413,"path_740":"http:\/\/www.tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/2_4_0.jpg?itok=DqZVHohh"}}},"media_ids":["257371"],"related_links":[{"url":"http:\/\/arxiv.org\/pdf\/1307.0421.pdf","title":"http:\/\/arxiv.org\/pdf\/1307.0421.pdf"}],"groups":[{"id":"60783","name":"MRSEC"}],"categories":[{"id":"42941","name":"Art Research"}],"keywords":[{"id":"9116","name":"epitaxial graphene"}],"core_research_areas":[{"id":"39451","name":"Electronics and Nanotechnology"},{"id":"39471","name":"Materials"}],"news_room_topics":[],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}}}