CAREER: Structure-specific Nanoscale Dynamics Studied by Nonlinear and Magneto-optical Spectroscopy

This CAREER award by the Macromolecular, Supramolecular, and Nanochemistry (MSN) program supports work by Professor Kenneth Knappenberger at Florida State University -endowed to develop advanced spectroscopic techniques for the investigation of the size-dependent and structure-specific optical properties of gold nanostructures ranging from quantum-confined clusters (< 2 nm) to plasmon-supporting particles (> 2 nm). Specifically, the PI, along with graduate students, will develop femtosecond time-resolved magneto-optical techniques to study both the electronic structure and excited state-dynamics of size-selected gold nanoclusters. The PI will also develop a nonlinear microscopy platform capable of single-particle measurements. These data will inform on plasmon modes that result from hybridization of gold nanostructures in both small aggregates and lithographically formed arrays. Advances made in these two areas will be merged to describe plasmon-mediated electric-dipole transitions, and the nonlinear imaging facility will be extended to a magneto-optical platform capable of state-resolved plasmon-enhancement measurements.

The award will allow Professor Knappenberger to develop advanced measurement technologies to investigate systematically the nanoparticle structure-function interplay. This research will impact several technical areas: solar-energy conversion, national security, trace-level analysis and high-contrast biomedical imaging. Moreover, new facilities, capable of providing temporally and spatially resolved magneto-optical data, will be established. As a result, the group will establish a unique expertise that can be applied to problems in many areas of science and technology that require spin and oxidation state information.

This program will educate both undergraduate and graduate students in an interdisciplinary environment at Florida State University and will benefit from close interactions with the National High Magnetic Field Laboratory. Also, in an effort to improve understanding and stimulate interest in science and technology among a diverse group of high school students, Professor Knappenberger will work closely with a high school teacher to introduce new instrumentation into an image-based chemistry curriculum. Finally, as an extension of the investigator's classroom teaching, a series of instructional visual materials will be developed to describe proper use of scientific instruments to a diverse audience.