Abstract

A chirped pulse amplification laser configuration capable of particle acceleration through the driving of a plasma beatwave into saturation before modulation instabilities can grow is reported. The configuration is based on generating a single sub-ps, broad bandwidth pulse (~16 nm) and stretching and filtering to select two wavelength components (separation ~ 7 nm). The two spectral components are temporally stretched (to >100 ps) and separated (by ~ 1 ns). The pulses are then amplified in a single Nd:glass chain to greater than 15 J per pulse Using a single pass reflective grating compressor the pulses are temporally compressed to between 2 and 5 ps and automatically synchronised. Moreover, the system is capable of introducing a chirp into the actual beat, such that the compressed pulses can compensate for relativistic detuning of the plasma wave. The optimum laser amplification and recombination configuration for generating a saturated laser driven beatwave is presented and options for future work discussed.

© 2000 IEEE