A systematic study of the excitonic properties of carbon nanotubes is proposed. Optical Absorption, Photoluminescence and Photoluminescence Excitation Spectroscopy will be carried out by researchers at Arizona State University (ASU), the Universidad Autonoma de Madrid (Spain) and Clemson University. The special materials needed for these studies will be synthesized at Clemson University, and theoretical support will be provided by researchers at the University of Modena (Italy). The project is expected to have a broad societal impact. The recent fabrication of nanotube heterojunctions and the discovery of doping mechanisms suggest that carbon nanotubes may play an important role in future generations of optoelectronic devices. The understanding of excitons in these materials is a fundamental scientific prerequisite for any such application. A special emphasis will be placed on fostering scientific education. Existing programs at ASU will help attract minority and high-school students. Interdisciplinary graduate courses on Raman spectroscopy and Excitons will be taught at Arizona State University by the European partners. Course notes will be disseminated via the Internet. The program will also support experimental research in Europe by US graduate students.
Technological advances that improve the standard of living of our citizens depend, to a great extent, on the development of new materials. These advances are invariably preceded by intense fundamental research. In this project it is proposed to study the basic properties of carbon nanotubes, a new class of materials with an intriguing technological potential. The specific purpose of this project is to study "excitonic effects" in the absorption and emission of light by carbon nanotubes. Excitonic effects result from the attractive force between an electron that is excited by the light and the positive charge it leaves behind. These effects are of fundamental importance in conventional semiconductors, but in the case of carbon nanotubes they have not been studied in any detail. The required nanotube samples will be prepared at Clemson University. Optical measurements will be performed at Clemson, Arizona State University, and at the Autonomous University in Madrid, Spain. Theoretical support will be provided by collaborators at the University of Modena, Italy. These international collaborations will make it possible for US graduate students to do research work abroad.
This NSF project is co-funded by the Office of Multidisciplinary Activities, and the Divisions of Material Research (Condensed Matter Physics), International Office (Western Europe) and a Cooperative Activity in Materials Research between the NSF and Europe (NSF 02-135). This project is being carried out in collaboration with the Autonomous University in Madrid, Spain and University of Modena, Italy.
