INSTITUTE OF PHYSICS, UNIVERSITY OF GREIFSWALD
CHAIR OF EXPERIMENTAL PHYSICS: INTERFACE PHYSICS
Experimentalphysik II - Grenzflächenphysik, Prof. Dr. Rainer Hippler
Dusty hydrocarbon plasma - Spectroscopic diagnostics with quantum cascade laser
In our research group some types of hydrocarbon-containig plasmas are explored. Namely, the low-pressure RF-discharge, which is representative for dusty plasma, and high-pressure DBD-discharge, used for conversion of methane to hydrogen and higher-order hydrocarbons. A proper diagnostics for particle number dencities would aid to bring the underlying chemistry to light. For this purpose the laser absorption spectroscopy is used. In my case it is based on quantum cascade laser, which recently has become an alternative to a conventional tunable diode laser. The system QMACs we have can be tuned over 4 cm-1 in the vicinity of 848 cm-1 , which allows one to trace ethane, ethen and ammonia concentrations with time resolution about 0.1 seconds.