Monday, October 18, 2010 12:00 Noon
Ballroom C, Albuquerque Convention Center

 

Louis Brus was educated in Chemical Physics at Rice University and Columbia University. In 1973 he joined the chemistry and materials research area of Bell Laboratories in Murray Hill, NJ. He returned to Columbia in 1996, where he is now S. L. Mitchill Professor of Chemistry. He is a member of the US National Academy of Sciences, and in 1998 was the Chairman of the Board of Trustees of the Gordon Conferences. He has won the APS Langmuir Prize, the ACS Chemistry of Materials Prize, the OSA Wood Prize, and in 2008 the inaugural Kavli Prize in Nanoscience.

Carbon Nanotubes and Single Sheet Graphene

We explore the fundamental nature and dynamics of excited electronic states in single wall carbon nano-tubes (SWNT). Near infrared two photon luminescence excitation spectra quantitatively reveal strongly bound exciton excited states in semiconducting tubes. Electron-electron interactions are very strong. In order to characterize metallic and semiconducting individual tubes, we observe both resonant Rayleigh and Raman scattering. In single sheet graphene, the Fermi level, and metallic versus molecular character, are strongly affected by environmental chemical doping. This is revealed by the Raman spectrum. Two layer graphene can develop a band gap in the presence of a perpendicular electronic field. We observe that band gap can also open in three layer and thicker graphenes, due to surface doping by adsorbed species.