Current research spurred by the MTW laser includes laser–matter interactions, ultrafast laser science, laser and radiation diagnostic development, and materials research. Experimental regimes are achieved that are inaccessible with conventional table-top laser systems and without the cost and schedule overhead associated with large-scale facilities. University of Rochester faculty, LLE staff, visiting scientists and students from external institutions, as well as graduate, undergraduate, and local high school students have performed research facilitated by the MTW laser.
The MTW laser currently provides picosecond-scale laser pulses at energies greater than 10 J and will be ramped up to 100 J. Intense laser–solid interactions generate a unique, high-current electron source with relativistic energies. Uncertainties exist in how this hot-electron source is generated and how it couples to overdense plasmas. Important applications rely on a detailed knowledge of these processes, including rapid heating for fast-ignition fusion and energy deposition in solid material for flash radiography, isochoric heating, and x-ray scattering experiments. The aim of the research performed at this facility will be to characterize and optimize the hot-electron source generated with the MTW laser and to understand the underlying energy-coupling mechanisms.
Upgrades to the MTW laser will significantly scale up the peak THz electric field of pulsed THz radiations that can be achieved with conventional laser systems that deliver only pulse energies of the order of a few mJ. Currently, laser-based THz sources can reach a peak THz electric field of the order of 1 MV/cm pumped by laser pulses of ~30 fs and a few mJ. Such a peak electric field can be marginally used to investigate nonlinear interactions between pulsed THz waves and various materials. The peak electric field of laser-based THz radiations generated from laser-induced gas plasmas is mainly limited by the optical pulse energy and pulse duration of the pump laser. With the upgraded laser system, we expect an improvement of 3 or 4 orders of magnitude in the THz peak electric field. THz electric fields as high as 1 GV/cm can push electrons or other charged particles in novel materials (such as metamaterials and graphenes) into highly nonlinear regimes, which will open a new avenue toward nonlinear THz optics and optoelectronics.
