Boston Chapter of the IEEE Photonics Society

Wed
Nov 2, 2005
8:30 PM
 

MIT Lincoln Laboratory
 

High Power THz Generation

Dr. Gwyn Williams, Jefferson Lab, Newport News, VA

Abstract:  Light is one of our prime tools for understanding both the form and function of materials ranging from superconductors to proteins, yet there is a gap in the electromagnetic spectrum between electronics and photonics at frequencies around 1 THz.  Recently at Jefferson Lab, (Nature 420 153-156 (2002)), we demonstrated the production of THz light that was 10,000 times brighter than any previous source. We have subsequently taken this work to higher powers and constructed a user facility for its exploitation.  We will discuss the physics of the new generation of accelerator-based light sources which we used for these experiments, and further describe future possibilities for yet higher power

Biography:  Gwyn Williams is a Senior Physicist and Basic Research Program Manager at the Free Electron Laser facility (FEL) at Jefferson Lab in Newport News, Virginia, and a Fellow of the American Physical Society.  He is also head of the JLab high power THz facility.  Since obtaining his PhD from Sheffield University in the UK in 1971, Gwyn has co-authored 220 research publications, most of them in the surface science area, and several book chapters.  The bulk of his career has been at Brookhaven National Laboratory but 5 years ago he moved to Jefferson Lab in Virginia.  Gwyn’s research has involved understanding the fundamental physical behavior of materials and surfaces via photoemission studies of the electronic structure, and infrared studies of the vibrational dynamics of adsorbates.  His research has motivated a lifelong parallel development of ultra-bright light sources as probes, a path that recently took him into the THz regime using the ultrafast facilities that are part of the FEL facility.  He was the 1990 recipient of an R&D 100 Award for developing a wavefront dividing interferometer for use with ultrabright sources.  His current research programs involve studies of the frequency dependent conductivity of gold nanowires on vicinal silicon surfaces and of the dynamics of bonding vibrational modes in both time and frequency domains.  Gwyn currently serves on a number of scientific advisory committees for large facilities around the world, has served as editor for several journals, and currently is on the editorial board of the Review of Scientific Intrsuments, and Synchrotron Radiation News.