Spike Trains of Uneven Duration and Delay Optimally Designed for HEDLP and IFE

Spike Trains of Uneven Duration and Delay, or STUD pulses promise to revolutionize how we do IFE in the future. By controlling laser plasma instabilities, whole new approaches to hydrodynamically stable and robust IFE designs become possible with efficient lasers (such as the Green option with glass lasers). In order to stop the uncontrolled growth of laser-plasma instabilities due to the coherence of the laser, in STUD pulses the laser is broken up into a series of uncorrelated spikes which have durations and delays of the order of the growth time of the instabilities that are to be mitigated and shorter than the damping time of the plasma modes involved in the instabilities. The interplay of hot spot redistribution and polarization change and plasma induced smoothing which will be different for each spike in a train of spikes will make the recurrence of significant hot spot intensity spatial overlap inside the plasma very low. This will guarantee that the driven waves will damp between in between these long recurrence times. This in turn will guarantee only incoherent addition of spurts of growth in uncorrelated hot spots over thousands of spikes. Linear superposition as opposed to exponential growth itself implies strict control over LPI never before achieved. This is the new vision of LPI control with STUD pulses which we plan to study, implement and explore further with this SBIR in collaboration with colleagues from LANL, FSC Rochester and NRL. The specific theoretical and computational steps required to prepare for a Phase II which will be also rich in experiments and optimization that is empirically driven, are carefully sketched in the proposal. Commercial Applications and Other Bene