摘要
Broadband low-coherence light is considered to be an effective way to suppress laser plasma instability.Recent studies have demonstrated the ability of low-coherence laser facilities to reduce back-scattering during beam–target coupling.However,to ensure simultaneous low coherence and high energy,complex spectral modulation methods and amplification routes have to be adopted.In this work,we propose the use of a random fiber laser(RFL)as the seed source.The spectral features of this RFL can be carefully tailored to provide a good match with the gain characteristics of the laser amplification medium,thus enabling efficient amplification while maintaining low coherence.First,a theoretical model is constructed to give a comprehensive description of the output characteristics of the spectrum-tailored RFL,after which the designed RFL is experimentally realized as a seed source.Through precise pulse shaping and efficient regenerative amplification,a shaped random laser pulse output of 28 mJ is obtained,which is the first random laser system with megawatt-class peak power that is able to achieve low coherence and efficient spectrum-conformal regenerative amplification.
基金
support of the National Natural Science Foundation of China(Grant Nos.62075030,62075201,and 11904339)
the Sichuan Provincial Project for Outstanding Young Scholars in Science and Technology(Grant No.2020JDJQ0024)。
