报告摘要：Graphene, a single atomic layer of hexagonal carbon lattice, constitutes the ultimate two-dimensional structure. When the graphene is folded up, it forms single-walled carbon nanotubes, a prototypical one-dimensional system. Such two- and one-dimensional graphitic carbon systems exhibit many fascinating optical behaviors. In this talk, I will describe the remarkable gate-dependence of the optical transitions in graphene. These optical transitions can be further varied through interlayer coupling as observed in graphene bilayers, and through quantum confinement effect as realized in single-walled carbon nanotubes. For the investigation of carbon nanotubes, we develop optical spectroscopy techniques capable of probing individual carbon nanotubes, Using such techniques, we demonstrate the correlation between the nanotube electronic transitions and their atomic structures, and reveal the distinct characteristics of optical transitions in one dimension.

报告人简介：Prof. Feng Wang received his BS in Physics from Fudan University in 1999 and his PhD in Physics from Columbia University in Oct. 2004. He was a postdoctoral Researcher at Columbia from Oct. 2004 to Jul. 2005, a Miller Research Fellow at the University of California at Berkeley from Aug. 2005 to Jun. 2008, and an Assistant Professor of UC Berkeley from Jul. 2007. His main research interests include: Optical spectroscopy of nanostructures, including carbon nanotubes and graphene; Ultrafast carrier dynamics in nanostructures; Nonlinear optical spectroscopy of complex oxide surfaces; and Light-matter interactions in low-dimensional systems. Major honors include: T. D. Lee Scholarship, Fudan University (1995); Charles Townes Fellowship, Columbia University (2004); Miller Fellow, University of California, Berkeley (2005); Alfred P. Sloan Research Fellow (2008); and Outstanding Young Researcher Award, Overseas Chinese Physics Association (2008).