Feasibility study of a high power laser system with beam combination method using phase conjugation mirrors of a stimulated Brillouin scattering for generating an ultra high power output with a high repetition rate over 10Hz

A beam combination laser with stimulated Brillouin scattering phase conjugate mirrors (SBSPCMs), 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 future. In order to develop the beam combination laser with the 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 vale 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 2 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 10Hz, in this paper. (author)