论文信息 - Investigation of stimulated brillouin backscattering of nanosecond CO2 laser radiation from an extended underdense plasma

Investigation of stimulated brillouin backscattering of nanosecond CO2 laser radiation from an extended underdense plasma

Stimulated Brillouin backscattering (SBS) of nanosecond CO2 laser radiation is investigated from an homogeneous extended plasma for well defined interaction conditions. It is found that SBS saturates at the theoretical limit near 100% Growth of SBS ion-waves starts from near thermal-wave amplitudes. Theoretical and observed SBS threshold fluxes agree within the 50% error bounds of these values. It is pointed out that self focusing does not greatly affect SBS under the conditions investigated. SBS thresholds depend on plasma density and focal spot diameter. It is indicated that an equilibrium between inverse bremsstrahlung absorption and classical heat conduction can explain several aspects.

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