Event
Robert Schwartz Doctoral Defense
Friday, June 10, 2022
10:00 a.m.
IREAP Large Conference Room, Room 1207
Meredith Pettit
301 405 4951
mpettit1@umd.edu
Notice of Doctoral Defense
Name: Robert Schwartz
Dissertation Title: Mid-Infrared Laser Driven Avalanche Ionization and Low Frequency Radiation Generation
Date and Time: Thursday June 9, 2022, 9:00 AM
Location: IREAP Large Conference Room
Dissertation Committee Chair: Howard Milchberg
Committee:
Phillip Sprangle
Ki-Yong Kim
Brian Beaudoin
Timothy Koeth
Abstract:
In this dissertation, we discuss the applications of intense mid-infrared laser interactions in three main topics. First, we demonstrate and discuss the remote detection of radioactive materials using avalanche breakdowns driven by picosecond, mid-infrared laser pulses. In the presence of radioactive materials, an enhanced population of free electrons and weakly bound ions are created in air. Laser driven avalanche ionization is a powerful tool for amplifying and detecting this weak signature, allowing for detection at standoff distances beyond the stopping distance of the radioactive particles. This technique can be applied more generally to the detection of any low density plasma. In the second section, we apply a similar method to measure laser ionization yields in atmospheric pressure gas across an extremely wide range. Finally, we demonstrate and discuss the generation of THz and low harmonics from two-color mid-infrared laser pulses. This technique allows for the generation of highly efficient, ultra-broadband coherent radiation.