Miniature microwave plasmas with diameters of approximately 1 mm were generated in high-pressure argon (0.1–5.0 MPa) using a microgap electrode. The microwave power required to sustain plasmas was 1–10 W, depending on the pressure. Strong electron-neutral bremsstrahlung emission, indicating an electron temperature of approximately 12000 K, was observed at high pressures (>1 MPa), and electron densities estimated from Stark broadening revealed high values on the order of 1023 m%3. The analysis confirmed that the coefficient for the pressure shift of the Ar I line at 696.5 nm reported by Copley and Camm can be extended to 5 MPa.
ASJC Scopus subject areas
- Physics and Astronomy(all)