Dr. Hui Zhao

University of Kansas

Nonlinear optical studies of electronic transport in semiconductors

102 Cardwell Hall

October 27, 2014

4:30 p.m.

Electronic transport on nanometer dimensions is of fundamental importance in semiconductor nano-electronics. In this talk I will discuss our recent experimental studies of ballistic charge and spin transport on nanometer length scales by using ultrafast nonlinear optical techniques. I will discuss optical injection of ballistic currents through a coherent control technique utilizing quantum interference between one-photon and two-photon absorption pathways. I will then describe how to study the dynamics of these ballistic currents by tracking the position of the carriers with 100-femtosecond temporal resolution and sub-nanometer spatial detection capability. I will discuss second-order nonlinear optical effects induced by the spin and charge currents, and show that these effects can be used for a direct, nondestructive, and real-time imaging of these currents.

Hui Zhao is an Associate Professor in the Department of Physics and Astronomy at the University of Kansas.
Email: huizhao@ku.edu; Web: http://ultrafast.ku.edu