Pushing the Limits of Polarization Dependence Nonlinear Spectroscopy
Florencio Eloy Hernández, Ph.D.
Professor, Department of Chemistry and College of Optics & Photonics
February 21, 2019
Location: Physical Sciences Building 160/161
Networking, drinks and appetizers at 6:30 p.m. and talk begins at 7:00 p.m.
During the last few years my group built a particular interest for the fundamental understanding of the nonlinear optical properties of chiral structures with pivotal role in living systems, an invaluable applications in combinatorial methodologies for catalyst discovery and the design of negative refractive index metamaterials at optical frequencies. Chiroptical activity is commonly quantified in terms of circular dichroism (CD) and optical rotatory dispersion (ORD). However, the linear nature of these effects limits their application in the far and near-UV region in highly absorbing and scattering biological systems. In order to surmount this barrier, in recent years we made important advancements on a novel nonlinear, low-scatter, long-wavelength CD approach called two-photon circular dichroism (TPCD).
During this seminar I will present a descriptive analysis of the optics principles behind a unique differential technique that allows to measure the small TPCD signal (the double L-scan), and its significances using pulsed lasers. Then, I will introduce the existent theoretical and computational approaches that opens a route to calculate and model TPCD as molecular systems. Finally, I will illustrate, through the analysis of different effects in a family of biaryl derivatives, the remarkable potential of this novel spectroscopy tool to understanding chiral systems.