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The radiation transport effect on pellet implosion and the Rayleigh-Taylor (R-T) instability are studied in a light-ion beam (LIB) inertial confinement fusion (ICF) by numerical simulation and analytic work. First, we present the nonuniformity-smoothing effect of the radiation transport on implosion symmetry in an LIB ICF fuel pellet. The 2-D implosion simulation shows that the initial nonuniformity can be smoothed out well in an LIB ICF pellet; for example, the initial nonuniformity of 6% is smoothed to 0.07% during the implosion phase. In addition, linear analyses for the R-T instability under nonuniform acceleration in space and under radiation are also performed: The nonuniform acceleration field in space does not change the growth rate (γ) of the R-T instability. However, this nonuniformity may suppress the growth itself of the R-T instability. Radiation may reduc the growth rate (γ).

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Nonuniformity of heavy-ion-beam (HIB) illumination is one of key issues in the HIB inertial confinement fusion (ICF): implosion symmetry should be less than a few percent in order to compress a fuel sufficiently and release fusion energy effectively. In this paper a new HIB illumination scheme is presented in order to realize a robust illumination scheme against a displacement of a direct-driven fuel pellet in an ICF reactor. It is known that the HIB illumination nonuniformity is sensitive to a little pellet displacement from a reactor chamber center; a pellet displacement of only 50–100μm was tolerable in the conventional HIB illumination schemes. In this paper by three-dimensional computer simulations a new robust HIB illumination scheme was found, in which a 200–300μm displacement is allowed.

Nanoscale polymer movement is induced by a tightly focused laser beam in an azo-polymer film just at the diffraction limit of light. The deformation pattern that is produced by photoisomerization of the azo dye is strongly dependent on the incident laser polarization and the longitudinal focus position of the laser beam along the optical axis. The anisotropic photo-fluidity of the polymer film and the optical gradient force played important roles in the light induced polymer movement. We also explored the limits of the size of the photo-induced deformation, and we found that the deformation depends on the laser intensity and the exposure time. The smallest deformation size achieved was 200 nm in full width of half maximum; a value which is nearly equal to the size of the diffraction limited laser spot.