Reduction of the Rayleigh-Taylor instability growth with cocktail color irradiation

Abstract

A novel method for reducing the Rayleigh-Taylor instability (RTI) growth in inertial confinement fusion (ICF) targets is reported. It is well known that high-density compression of ICF targets is potentially prevented by the RTI. Previous studies [K. Shigemori et al., Phys. Rev. Lett. 78, 250 (1997), S. G. Glendinning et al., Phys. Rev. Lett. 78, 3318 (1997), and H. Azechi et al., Phys. Plasmas 4, 4079 (1997)] have indicated that nonlocal electron heat transport enhances the effect on the ablative stabilization of the RTI growth with long wavelength laser irradiation. Planar target experiments, using a small fraction of a long wavelength laser (λ=0.53 or 1.05μm) in addition to the main drive laser (λ=0.35μm), were conducted to verify the RTI reduction by inducing the effect of the nonlocal electron heat transport. The measured RTI growth rate for this “cocktail-color” laser irradiation was clearly reduced from that for the “single-color” short-wavelength laser irradiation. The experimental growth factors are in good agreement with the ablative RTI formula coupled with a one-dimensional Fokker-Planck simulation code.