Education

1. Multidimensional Spectroscopy of Carbon Nanotubes:A new tool for exploring dynamics in NanomaterialsTobias Hertel, Vanderbilt University, DMR 0606506 Exploring spectral correlations of charge and energy transfer processes through multidimensional pump-probe excitation spectroscopy provides a new tool for a better understanding of fundamental photophysical properties of nanomaterials. Earlier this year we published results from preliminary work using manual tuning of an optical parametric amplifier (OPA), Fig. right top (J. Phys. Chem. C 111 (2007) p3831). We have since modified our OPA using stepper motors and developed a Labview based simplex algorithm for feedback controlled multidimensional optimization of the amplifier performance. This enhances the speed at which pump-probe excitation spectra can be taken by over one order of magnitude (Fig. right bottom)and - combined with higher accuracy if compared to manual tuning – allows to explore dynamical and spectral correlations in unprecedented detail. Spectroscopic investigations of metallic nanotube samples are under way.

2. Multidimensional Spectroscopy of Carbon Nanotubes:A new tool for exploring dynamics in NanomaterialsTobias Hertel, Vanderbilt University, DMR 0606505 Education Two graduate- and one undergraduate students,as well as a high school student are involved in work related to this project. One of the graduate students (Jessica Thompson) is funded over the summer to develop a new optics kit for the Vanderbilt Student Volunteers for Science outreach program which provides new hands on experiences and education for middle school children in the Nashville Metro area. Sergey Novikov, an undergraduate REU student supported through PHY-0649123makes use of the instrument during his summer studies. Kyle Broach, from the gifted student program of Ravenwood High School contributes to and works on the setup of simple optics experiments in our lab one afternoon per week. Societal Impact The exploration of photophysical properties of novel materials is key to understanding their potential for use in light emitting or detecting devices, photovoltaics or biomedical applications. The development of new enabling spectroscopic techniques and instrumentation along with the development of new materials facilitates the design and transitioning of new discoveries from the lab to industrial product development. The laser company Coherent has expressed interest in the technology and has scheduled a campus visit to learn about our experience with the instrument.