Beyond the Gouy-Chapman Model with Heterodyne-Detected Second Harmonic Generation
Abstract
We report ionic strength-dependent phase shifts in second harmonic generation (SHG) signals from charged interfaces that verify a recent model in which dispersion between the fundamental and second harmonic beams modulates observed signal intensities. We show how phase information can be used to unambiguously separate the chi(2) and interfacial potential-dependent chi(3) terms that contribute to the total signal and provide a path to test primitive ion models and mean field theories for the electrical double layer with experiments to which theory must conform. Finally, we demonstrate the new method on supported lipid bilayers and comment on the ability of our new instrument to identify hyper-Rayleigh scattering contributions to common homodyne SHG measurements in reflection geometries.
Keywords
Cite
@article{arxiv.1903.05707,
title = {Beyond the Gouy-Chapman Model with Heterodyne-Detected Second Harmonic Generation},
author = {Paul E. Ohno and HanByul Chang and Austin P. Spencer and Yangdongling Liu and Mavis D. Boamah and Hong-fei Wang and Franz M. Geiger},
journal= {arXiv preprint arXiv:1903.05707},
year = {2019}
}
Comments
21 manuscript pages, four figures, 10 pages supporting information included, pre-edited version