Electron beam generation significantly influences the performance of vacuum-based high power electromagnetic (HPEM) devices. AFRL currently pursues a number of research efforts involving the generation of electron beams with novel materials, as well as investigating the physics of electron emission under a variety of conditions i.e. from DC to 10s ns pulse width. AFRL's Directed Energy Directorate (AFRL/RD) is interested in the development of laboratory-scale experiments and associated diagnostics for the purposes of validating analytical and computational electron emission models. The physics of electron flow and its effects on HPEM generation will also be explored analytically and using computational methods.    

Additionally, AFRL/RD is interested in developing a fundamental understanding of plasmas and secondary electrons generation by electrons bombardment with metal surfaces within the HPEM devices. Their effects on HPEM generation will also be explored experimentally for the purposes of advancing analytical and computational models.

It is recommended that applicants have a strong background in electron emission physics and familiarity with HPEM sources and generation. Knowledge in theoretical and computational plasma physics would also be beneficial for interested applicants. 

References:

1. "Schottky conjecture and beyond", D Biswas, Journal of Vacuum Science & Technology B 38, 023208 (2020).

2. "Effect of Nonuniform Emission on Miram Curves", D Chernin, YY Lau, JJ Petillo et. al, IEEE Transactions on Plasma Science, Vol. 48(1) (2020). 

3. "Pulse shortening in recirculating planar magnetrons", NM Jordan, GB Greening, SC Exelby, DA Packard, YY Lau et. al, IEEE Transactions on Electron Devices 65(6), 2354-2360 (2018).

key words

High Power Electromagnetics; Electron Beam; Plasmas; Computational Physics; Particle-in-cell; High Power Microwave

Citizenship:  Open to U.S. citizens

Level:  Open to Postdoctoral and Senior applicants