We have established the intensity limits for propagation of a frequency-doubled ($2\omega$, 527 nm) high intensity interaction beam through an underdense large-scale-length plasma. We observe good beam transmission at laser intensities at or below $2\times {10}^{14}\mathrm{W}/{\mathrm{c}\mathrm{m}}^2$ and a strong reduction at intensities up to ${10}^{15}\mathrm{W}/{\mathrm{c}\mathrm{m}}^2$ due to the onset of parametric scattering instabilities. We show that temporal beam smoothing by spectral dispersion allows a factor of 2 higher intensities while keeping the beam spray constant, which establishes frequency-doubled light as an option for ignition and burn in inertial confinement fusion experiments.

• Received 4 March 2004

DOI:https://doi.org/10.1103/PhysRevLett.94.085005