ECLIPSE: Ultrafast photoemission induced non-equilibrium plasmas

Michigan State University, East Lansing MI

Investigators

Abstract

This award supports a study of time-dependent formation and evolution of a plasma generated using photoemission driven by ultrafast lasers. Plasmas are often created through electrical breakdown of neutral gas to generate charged particles, but it is also possible to create a plasma by shining a laser on a metal surface causing electrons to be ejected by a process called photoemission. Recent developments in ultrafast nano-optics have made it possible to create plasmas using photoemission that have specific properties in the spatial and velocity-distribution of the resulting electron population. A better understanding of the fundamental physics of this process will be transformative for both basic scientific research and emerging applications, such as plasma based high speed electronics and microchips, plasma catalysis and processing, and robust ultrafast laser detectors. The project will theoretically and numerically study how the plasma electrons evolve from a given anisotropic velocity distribution due to photoemission to a thermalized state. Plasmas with precise seeding offer a widely accessible laboratory platform to study fundamental plasma physics, such as the evolution of plasma waves and instabilities. In addition, by tailoring the photoemission pulse properties and repetition rate, the research explores a possible new way of direct normal glow plasma generation using photoemission, by skipping Paschen’s breakdown, which will help to eliminate circuit stress, reduce plasma contamination, and improve system reliability. Plasma generation and control using cheap, low intensity light sources will also be explored, with the help of plasmonic resonant enhanced photoemission. Furthermore, this research may enable a new paradigm of few-cycle laser characterization for carrier-envelope phase (CEP) sensitivity with significantly enhanced signal strength using plasmas. Sub-optical-cycle control of plasmas is also important to potentially transformative applications, such as precise electrification of chemical reactions, chip-scale plasma accelerators, ultrahigh speed plasma electronics, and ambient-condition testbeds for strong-field nano-optics. 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.