Infrared Oscilloscopes: Sampling 30-THz Waveforms for Next-Generation Spectroscopy

Dr. William Putnam
Assistant Professor ECE Department, UC Davis, Davis, CA

Cerent Engineering Science Complex, Salazar Hall 2009A
3:00 PM

Abstract: In electronic devices like field-effect transistors, applied electric fields, up to hundreds of gigahertz in frequency, control electron motion. Recently, it has been demonstrated that the electric fields of ultra-intense laser pulses, i.e. electric fields in the tera- to petahertz (THz to PHz) regime, can similarly control electric currents around gas-phase atoms. In this talk, I will describe recent efforts to extend these early demonstrations of THz- and PHz-speed electronics from gaseous media to solid-state, microelectronic devices. Specifically, I will describe nanoantenna-based devices in which electric currents can be switched on and off by individual oscillations of the electric field of an infrared laser pulse. I will show that these devices can be used to sample >30-THz electric field waveforms in the time domain, and I will overview one of the exciting potential applications of these devices: field-resolved infrared spectroscopy.

Bio: William Putnam received his Ph.D. in EECS from MIT as well as undergraduate degrees in EECS and physics. Following his Ph.D. he held postdoctoral positions at MIT and the Center for Free-Electron Laser Science (CFEL) at the University of Hamburg, Germany. After his postdoctoral work and prior to joining the faculty at UC Davis, William spent several years as a staff scientist at Northrop Grumman’s basic research laboratory, NG Next where he worked on ultrafast electronics and frequency comb technology. From his undergraduate years to his postdoctoral work to his time in industry, William’s research has centered around both fundamental and applied studies of optics and quantum electronics.