Spatially Resolved Absorption Spectroscopy on a Microhollow Cathode Helium Plasma Using a Vertical-Cavity Surface-Emitting Laser

抄録

For the 1s2p(¹P) → 1s3d(¹D) transition at 667.815 nm of helium in a microhollow cathode plasma with a 300 µm diameter, we measured the absorption spectra with spatial resolution of 30 µm using a vertical-cavity surface-emitting laser diode. The spectra observed near the electrode at 10 kPa gas pressure showed asymmetry. By analyzing the observed spectra with Voigt functions including the DC Stark effect, we evaluated the gas temperature, electron density, electric field strength and 1s2p(¹P) atom density and produced their two-dimensional maps.