Broadband Two-Photon Absorption Spectroscopy for High-Repetition-Rate Lasers

University Of Kansas Center For Research Inc, Lawrence KS

Investigators

Abstract

Broadband Two-Photon Absorption Spectroscopy for High-Repetition Rate Lasers With support from the Chemical Measurement and Imaging Program in the Division of Chemistry, Professor Christopher Elles and his group at the University of Kansas are working to develop and implement new laser-based methods to measure and characterize the properties of molecules. The activation of molecules using intense laser pulses has important applications in many research fields, ranging from microscopic imaging of biological samples to the development of high-density optical data storage media. However, the best methods currently available for these applications are only accessible to research groups with specialized technical expertise, which are not necessarily the groups who make the materials. Working with both graduate and undergraduate students, Professor Elles is developing new techniques and instrumentation that will make these sophisticated measurements more widely accessible to the research community. By simplifying the process for characterizing the properties of laser-activated molecules, this work enables more rapid development of new compounds and new technologies, including diagnostic and therapeutic biomedical applications. The project also includes an integrated educational outreach program to help current and future high school science teachers develop new teaching materials that incorporate key concepts from contemporary research and address the Next Generation Science Standards (NGSS). The research team is developing more widely accessible methods for measuring broadband two-photon absorption (2PA) spectra using high-repetition rate femtosecond lasers. Current methods to measure 2PA spectra, including z-scan and two-photon excited fluorescence (2PEF), are limited to single-wavelength measurements and are not easily implemented by groups that do not specialize in nonlinear spectroscopy. To overcome these limitations, the group is working to design an integrated, one-box spectrometer that can be coupled with any existing femtosecond pulsed laser system to quickly and easily obtain accurate 2PA spectra, providing a valuable new tool for molecular spectroscopy. The team is working to develop new capabilities that include accurate absolute 2PA cross-sections, single-shot data acquisition, and on-the-fly imaging of 2PA spectra. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.