Professorial Lecture Series

"Terahertz Optoelectronics"
Professor Chao Zhang

Wednesday 26th October 2005, 14.G01, 12:30-1:30pm

Terahertz (THz) radiations (frequency of 1-20 THz) are important to many areas of scientific, industrial and medical research such as astronomical exploration, optical communication, medical diagnosis, agriculture, water resource, quality control of plastic package, etc. THz wave has been regarded as one of the ten leading technologies that will change the world in next decades (see Technology Review, Feb 04, www. technologyreview. com ).

THz frequency overlap with virtually all fundamental energies in nanometer electronic materials, from the Fermi energy to the sub-band energy gap. Because of this, understanding of properties of electronic materials in the THz regime is important to developing new THz emitters and sensors. Such devices are based on the fundamental changes in electronic and dielectric properties of materials in the THz frequency regime.

In this talk I will discuss the recent progress in terahertz optoelectronics. The key problem in developing new terahertz optoelectronic devices is the nonlinear coupling between electrons and the THz field. We have recently developed several theoretical and numerical methods to study the nonlinear optical and transport properties in electronic materials under THz radiation. New results on the free carrier absorption, plasma emission and photo-current response will be presented.

Chao Zhang
School of Engineering
Physics and Institute of Superconducting and Electronic Materials
University of Wollongong
Email: czhang@uow.edu.au
Web: http://www.uow.edu.au/~czhang/czhang.html