Characteristic Investigation of an Atmospheric-Pressure Microwave N2–Ar Plasma Torch

Impedance matching is implemented to stabilize an atmospheric-pressure waveguide-based N
₂
-Ar plasma torch with the aid of the use of swirl gas. Optical emission spectroscopy is employed to diagnose the plasma torch with respect to the population of the electronic state N
⁺
₂
(B
²
Σ
⁺
_u
) and N
₂
(B
³
Π
_g
) versus the absorbed power and the ratio of N
₂
component in the Ar-N
₂
mixture by the measurement of the emission of intensity. The qualitative discussion based on the reaction routes is delivered to interpret the experimental results well.