Control and ultra-short pulse generation in stimulated Raman backscattering

摘要

AstimulatedRamanscattering(SRS)isagreatconcernforlaserfusion,causinganenergyandsymmetrylossandtargetpreheating.Inparticular,fordominatingbackward-SRS(BRS),acomplexityofnonlinearsaturationwasrevealed.Recently,todeveloplasersatmulti-exawattsandbeyond,relevanttohigh-energyphysics,aproposedRamanamplificationbasedonBRSmetarestrictiveoperationwindow.Here,westressBRSgenericsthatduetoanonlinearfrequencyshift(relativistic/trappingeffect),itnonlinearlysaturateswithintermittentpulsations.A"breakup"ofManley-Roweinvariantsexplainsanon-steadysaturation.Further,acoherentpulsationBRSregimeisproposedforfemto-secpulsegenerationinathinexplodingfoilplasma,withparameterscalingsinvestigatedbyanalyticsandparticlesimulations...