Stabilizing effect of anisotropic thermal diffusion on the ablative Rayleigh-Taylor instability

Linear theory of the ablative Rayleigh-Taylor instability in anisotropic diffusive materials is presented. This analysis indicates that enhancing diffusion in a plane transverse to the mean longitudinal flow can strongly reduce the growth of the instability. In the context of inertial confinement fusion, it is shown that anisotropic diffusion can be achieved using a laminated ablator made of successive layers of different diffusive properties. Numerical simulations confirm the theoretical predictions and indeed exhibit a significant stabilization of the ablation front for laminated ablators.