Early stage time evolution of a dense nanosecond microdischarge used in fast optical switching applications
Abstract
The mechanism of high-voltage nanosecond microdischarges is studied by the self-consistent two-dimensional Particle-in-Cell/Monte Carlo Collisions model. These microdischarges were recently proposed for use as fast switches of visible light in Bataller et al. [Appl. Phys. Lett. 105, 223501 (2014)]. The microdischarge is found to develop in two stages. The first stage is associated with the electrons initially seeded in the cathode-anode gap. These electrons lead to the formation of a cathode-directed streamer. The second stage starts when the secondary electron emission from the cathode begins. In this stage, a rather dense plasma (∼1016 cm−3) is generated which results in the narrow cathode sheath. The electric field in this sheath exceeds the critical electric field which is necessary for the runaway electrons generation. We have found that the presence of these energetic electrons is crucial for the discharge maintenance.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Dec 01, 2015
- Source ID
- 10.1063/1.4939022
Entities
People
- Dmitry Levko
- Laxminarayan L. Raja
Organizations
- Air Force Office of Scientific Research
- University of Texas at Austin