Exciton Correlations in Semiconductors Probed by Ultrafast Spectroscopy

Date: 
Monday, November 20, 2006 (All day)
Speaker: 
Dr. Xiaoqin "Elaine" Li
Speaker's Institution: 
University of Texas at Austin

Exciton Correlations in Semiconductors Probed by Ultrafast Spectroscopy

 

Semiconductors serve as ideal model systems for the investigation of

many-body Coulomb correlations between excitons. In this talk, I will

introduce the concepts of a new spectroscopy tool: optical two-dimensional

Fourier transform spectroscopy. A two-dimensional spectrum correlates the

phase (frequency) evolution of the nonlinear polarization field during the

initial evolution and the final detection period. A single two-dimensional

spectrum can identify couplings between resonances, separate quantum

mechanical pathways, and distinguish among microscopic many-body

interactions.