Absolute parametric decay instability control by the complementary pump
Stepanov Institute of Physics NAS of Belarus - pr. Nezavisimostsi 68, 220072 Minsk, Republic of Belarus
2 IRAS Ioffe Institute - ul. Politechnicheskaya 26, 194021 St-Petersburg, Russian Federation
Accepted: 11 January 2011
The possibility of deep parametric decay instability suppression by launching a complementary (small power) pump wave possessing a slightly shifted frequency is demonstrated experimentally. This suppression is achieved at an additional pump wave frequency shift equal to the frequency separation of ion acoustic eigenmodes excited in plasma as a result of absolute parametric decay instability. The recovery of microwave power absorption at the second pump turn on is shown using measurements of the plasma luminosity and accelerated electron fluxes.
PACS: 52.35.Mw – Nonlinear phenomena: waves, wave propagation, and other interactions (including parametric effects, mode coupling, ponderomotive effects, etc.) / 52.50.Sw – Plasma heating by microwaves; ECR, LH, collisional heating
© EPLA, 2011