Event
Ph.D. Dissertation Defense: Stefan Waczynski
Thursday, January 16, 2025
2:00 p.m.
IREAP Large Conference Room (ERF1207)
Maria Hoo
301 405 3681
mch@umd.edu
ANNOUNCEMENT: Ph.D. Dissertation Defense
Name: Stefan Waczynski
Committee:
Prof. Howard Milchberg, Chair
Prof. Phillip Sprangle
Prof. Julius GoldharProf. Yanne Chembo
Prof. Ki-Yong Kim, Dean's Representative
Date/Time: Thursday, January 16, 2025 at 2 pm
Location: IREAP Large Conference Room (ERF1207)
Title: Application of Ultrafast IR Lasers to Remote Detection, Beam Steering and Terahertz Generation
Abstract
Abstract
Mid-infrared (mid-IR or MIR) and long-wave-infrared (LWIR) laser pulses with energies exceeding ~1 TW/cm2 constitute an interesting area of study for high energy laser physics, as for many applications, longer wavelengths provide positive scaling of laser-plasma interaction, and in some cases allow for the study of phenomena usually suppressed at shorter wavelengths. In this dissertation, we discuss applications of these systems in three primary topics. We start with a discussion of past and present experiments conducted at the University of Maryland (UMD) and Brookhaven National Laboratory (BNL) on the long-standoff detection of radiation with mid-IR and long-IR laser systems. In these experiments we drive and monitor avalanche breakdowns from seeding ions generated by a radiation source at standoff distances exceeding the propagation range of the radiation source by orders of magnitude and also discuss/explore both the possibility of scaling this method to greater range as well as the miniaturization of the systems driving this. We follow with experiments on using a long-pulse 1 µm laser to drive avalanche plasma grating structures for shot-to-shot diffraction of 4 µm light. We discuss the advantages and drawbacks of this methodology as well as scalability to standard laser wavelengths such as 800 nm. Finally, we discuss the generation of THz radiation by two-color mid-IR laser pulses, allowing for the generation of high efficiency coherent radiation in this band.
