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Schedule including this lecture.
Goddard Space Flight Center Engineering Colloquium
Date: Monday, May 21, 2001
Ultrafast optical phenomena refers to dynamical processes that occur in various forms of matter on the time scale of picoseconds (10-12s, ps) or femtoseconds (10-15s, fs). These phenomena have been relegated to the optical domain, primarily because only lasers have been fast enough to probe many of these processes. Laser pulses as short as 4.5 femtoseconds have been generated and utilized to study various physical phenomena. Ultrashort pulses of light have been utilized in fundamental studies of disciplines as diverse as semiconductor physics, lightwave transmission systems, and biological systems. Recently, for example, a group at Lawrence Berkeley Laboratory reported that the initial steps in the process of vision occur in approximately 200 femtoseconds. On another research front, ultrashort pulses have led to the generation of extremely high peak power pulses of approximately 100 TW (TW=Terawatt=1012W) and intensities of nearly 1020 W/cm2. One application of these intense pulses is in the generation of soft X-rays, for use in X-ray lithography. DWDM (Dense Wavelength Division Multiplexing) "hero" systems experiments with data transmission rates of 1 Tb/sec (1 trillion bits/sec) or more are now becoming fairly routine. Ultrafast optical phenomena continues to be a highly prolific field of fundamental and applied research. I will describe several of the techniques used by ultrafast opticists to measure events on this super short time scale and review some of the latest advances in the field.
He served as the 1990 Program Co-Chair, 1992 Conference Co-Chair, and 1996 Steering Committee Chair of the Conference on Lasers and Electro-Optics (CLEO 90, 92, 96). Dr. Johnson is a Fellow (1991), member of the Board of Directors (93-96; 00-03), and member of the Board of Editors (95-01) of the Optical Society of America (OSA); a Charter Fellow (1992) and Chair of the Nominations and Screening Committee (92-99) of the National Society of Black Physicists (NSBP); a Fellow (2000), member of the Board of Governors (93-95), and Chair, 1996 William Streifer Scientific Achievement Award Committee, of the IEEE Lasers and Electro-Optics Society (LEOS); a Fellow (1996) of the American Association for the Advancement of Science (AAAS); and a member of the American Association of Physics Teachers (AAPT). Dr. Johnson is President-Elect of the OSA and will serve as President in 2002.
Ph.D. (Physics) 1981, City College of the City University of New York [Ph.D. thesis research conducted at AT&T Bell Laboratories, Murray Hill, NJ -- Bell Labs Cooperative Research Fellowship]; B.S. (Physics, Magna Cum Laude) 1975, Polytechnic Institute of New York (now called Polytechnic University); born 5/23/54, Brooklyn, New York.
Colloquium Committee Sponsor: Dr. Eugene Waluschka
Engineering Colloquium home page: https://ecolloq.gsfc.nasa.gov