Walter Scott, Jr. College of Engineering

Graduate Exam Abstract

Jesse Wilson
Ph.D. Final
Jul 20, 2010, 2:00 PM
Engr B105
Odd-order Transient Susceptibility Perturbations in Raman Scattering
Abstract: The effect on an ultrashort probe pulse of an
impulsively prepared vibrational coherence is
described by effective linear and nonlinear
optical susceptibility perturbations. Linear
susceptibility perturbations modulate both the
amplitude and phase of a probe pulse. Three
spectral interferometry methods are described for
measuring this phase modulation, geared toward
spectral resolution, noise suppression, and rapid
data acquisition. Third-order nonlinear
interactions perturbations may be used to acquire
surface-specific Raman spectra. While second-order
spectroscopy is an established surface-specific
method, odd-order methods have been passed over
because the signal is generated in the bulk media.
We show that through a surface Fresnel modulation,
coherence-modulated third harmonic generation can
be used to obtain surface-specific vibrational
information. Bulk and interface contributions to
the vibrational signal are separated by scanning
the interface through the focus of the beam.
Adviser: Randy Bartels
Co-Adviser: N/A
Non-ECE Member: Jake Roberts
Member 3: Mario Marconi
Addional Members: N/A
Program of Study: