High-Intensity Tunable Light by Frequency Upshifting in Plasma Waves

Substantial progress has been made over the last several decades using particle beams or high-power lasers, such as the NSF ZEUS facility, to harness waves in plasma to build a new compact type of particle accelerator. Plasma wakefield particle accelerators promise to reduce mile-scale accelerator facilities to the size of a tabletop to provide x-rays for imaging viruses, diagnosing new materials, and for nuclear security applications. The goal of this project is to study the potential for these plasma waves to be able to directly 'accelerate' light instead of charged particles. The project will explore the limits of this technology studying how much the wavelength of light can be shortened, whether the light can have an arbitrary structure, and how bright the resulting radiation can be. Potential technological applications of such a bright, tunable light source include new tools for semiconductor etching technologies and diagnostics development for nuclear fusion energy research. The goal of this project is to study how plasma may be used as a space-time varying optical medium to generate new high-power, tunable sources of structured light by upshifting in electron plasma waves with relativistic phase velocity. The research program has several key objectives, including design of innovative plasma structures capable of manipulating laser light in both spatial and temporal domains within high-power laser systems, and building on recent theoretical work in 'photon acceleration' to explore the possibility of an all optical source of XUV light in plasma waves. Such a source would be coherent and have up to relativistic intensities. A ‘photon kinetic’ model will be developed and integrated into a particle-in-cell code for efficient simulation of XUV frequencies and beyond. Proof-of-principle experiments will be designed for facilities such as the NSF ZEUS laser facility at the University of Michigan or the potential future NSF OPAL laser facility at the University of Rochester. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.