Effect of symmetry requirements on the wavelength scaling of directly driven laser fusion implosions

The creation of a large, hot atmosphere surrounding a laser fusion target can produce symmetrization of incident beam illumination non-uniformities. This paper discusses the effect of laser wavelength on atmosphere formation and it is shown that for short-wavelength lasers there can be a significant penalty in implosion efficiency when the atmosphere is kept large enough to produce adequate symmetrization. Several ways to improve this situation are considered.