Measurements of nonlinear refractive index in scattering media.
Repository Usage Stats
We have recently developed a spectral re-shaping technique to simultaneously measure nonlinear refractive index and nonlinear absorption. In this technique, the information about the nonlinearities is encoded in the frequency domain, rather than in the spatial domain as in the conventional Z-scan method. Here we show that frequency encoding is much more robust with respect to scattering. We compare spectral re-shaping and Z-scan measurements in a highly scattering environment and show that reliable spectral re-shaping measurements can be performed even in a regime that precludes standard Z-scans.
More InfoShow full item record
Associate Research Professor in the Department of Chemistry
Dr. Fischer’s research focuses on exploring novel nonlinear optical contrast mechanisms for molecular imaging. Nonlinear optical microscopes can provide non-invasive, high-resolution, 3-dimensional images even in highly scattering environments such as biological tissue. Established contrast mechanisms, such as two-photon fluorescence or harmonic generation, can image a range of targets (such as autofluorescent markers or some connective tissue structure), but many of the most molecularly specif
James B. Duke Distinguished Professor of Chemistry
Our work focuses on the design and application of what might best be called novel pulsed techniques, using controlled radiation fields to alter dynamics. The heart of the work is chemical physics, and most of what we do is ultrafast laser spectroscopy or nuclear magnetic resonance. It generally involves an intimate mixture of theory and experiment: recent publications are roughly an equal mix of pencil- and-paper theory, computer calculations with our workstations, and experiments. Collabo
Alphabetical list of authors with Scholars@Duke profiles.