A method for aligning a femtosecond multi-petawatt coherent beam combining system

This work proposes a method for aligning a femtosecond multi-petawatt coherent beam combining system under quasi-static conditions. This method does not depend on the details of the laser system, and only exploits the information of the fluence distribution in the far field as the feedback for the control of a deformable mirror and a reflective mirror in each optical path to optimize the system in order to achieve coherent combining efficiency as high as possible. The full workflow consists of 8 steps among which the nontrivial ones are demonstrated through numerical simulations. This work provides a framework to manage the large-scale coherent combining laser systems.