Dynamic of ion density perturbations observed in a microwave-plasma interaction

The dynamical behavior of ion density perturbations propagated at low-frequency wave nature is experimentally observed in microwave-plasma interaction. An unmagnetized, inhomogeneous laboratory plasma irradiated by an obliquely incident microwave with maximum power P=10kW and pulse width approximately ion plasma period (τpi≈2π∕ωpi) is studied. The p-polarized electric-field component of the interacted microwave of frequency ω0 leads to a nonlinear phenomenon driven by the ponderomotive force by the process of resonance absorption at the critical layer where ω0=ωp is satisfied. The nonlinear ion density perturbations are created from the resonant layer and propagated to an underdense plasma as an electrostatic wave nature.