Title: Nonlinear imaging

Speaker: Dr. Zhiwen Liu, Pennsylvania State University

Time and place: 10:00-11:30a, Nov. 12th, 2012 (Monday), Room 616, Physics Building

Abstract:

This talk is mainly focused on two topics: coherent anti-Stokes Raman scattering (CARS) holography and nonlinear nanoprobes for imaging ultrafast optical fields. Specifically, I will first present our recent work on CARS holographic imaging, which combines the unique capabilities of both CARS and holography and can allow for chemically selective three-dimensional imaging without scanning. Both inline and off-axis digital CARS holography will be covered. I will then discuss a new class of nonlinear nanoprobe for probing ultrafast optical near fields, which is comprised of a fiber taper, a single nanowire attached to the taper, and functional nonlinear nanoparticles or nanocrystals attached to the nanowire. Both two-photon fluorescent and second harmonic nanoprobes will be presented. Application to characterizing ultrashort pulses in the focal point of an objective lens and in a hollow core photonic crystal fiber will be discussed.

Biography:

Dr. Zhiwen Liu is an associate professor of Electrical Engineering at the Pennsylvania State University. He received his Ph. D. degree in Electrical Engineering from the California Institute of Technology in 2002. After staying at Caltech for a year as a postdoctoral researcher, he joined the Penn State University in 2003. His current research at Penn State is focused on ultrafast nonlinear optics, optical imaging and spectroscopy, and nano-photonics. He received the CAREER award from the National Science Foundation in 2006.