Efficient Raman Amplification past Wavebreaking

.We present experimental results from the Raman amplification experimental platform at the University of Rochester’s Laboratory for Laser Energetics (LLE). This platform explores Raman amplification in a unique parameter space which includes a multi-joule pump and an adjustable-energy seed with seed intensities up to 7 x 10¹⁵ W/cm², which is significantly more intense than prior experiments. Initial experiments have demonstrated single-pass Raman amplification in multiple focal configurations with energy gain factors as high as 30x, energy transferred to the seed exceeding 220 mJ, and record efficiencies as high as 11.7%. The efficiency is observed to scale with seed intensity. For intense seed pulses, efficient amplification is seen well into the wavebreaking regime, as predicted by particle-in-cell simulations [1].



References:

[1] M. R. Edwards et al., Phys. Plasmas 22, 074501 (2015).