Highly repetitive high energy/power beam combination laser: IFE laser driver using independent phase control of stimulated Brillouin scattering phase conjugate mirrors and pre-pulse technique

Abstract

A beam combination laser with stimulated Brillouin scattering-phase conjugate mirrors (SBS-PCMs), which is expected to produce a high output energy and power with a repetition rate over 10 Hz, is a candidate for a practically useful laser fusion driver in the future. In order to develop the beam combination laser with SBS-PCMs, it is necessary to control the phase of each SBS wave whose phases are known as inherently random. We have proposed a new phase control technique and demonstrated experimentally that the relative phase difference between two SBS waves can be controlled to a certain value and locked to it with an accuracy less than λ/4. Additionally we have proposed and demonstrated a new technique to preserve the pulse shape of the SBS wave. Based on these experimental results, we have proposed two schemes of the new schemes for the high repetition and high energy/power beam combination laser system (laser fusion driver) using the SBS-PCMs of amplitude division and wave-front division techniques, which can operate with repetition rate over 10 Hz, in this paper.