基于高效率布里渊放大的高能量窄脉冲可调控涡旋激光技术研究

本项目提出采用液芯光纤或液芯简化光子晶体光纤布里渊放大器直接产生并高效率放大轨道角动量和偏振状态可调控涡旋激光的方法，为获得高能量窄脉冲可调控涡旋激光提供一条新的切实可行的技术途径。项目拟开展以下研究内容：轨道角动量和偏振状态可调控稳定涡旋激光的产生；窄脉冲可调控涡旋激光的高效率布里渊放大，包括涡旋激光布里渊放大理论、窄脉冲Stokes信号光的产生和放大后涡旋激光特性调控等方面。重点解决涡旋激光产生与放大过程中轨道角动量和偏振状态的调控机理和方法、涡旋激光的空域和时域行为特性控制，以及稳定性分析等关键科学问题。开拓高能量窄脉冲可调控涡旋激光新技术，解决传统光纤激光技术难以实现窄脉冲可调控涡旋激光高效率放大的技术瓶颈。期望获得能量大于1mJ，脉冲宽度小于5ns，能量转换效率大于40%的可调控涡旋激光。其成果将为激光加工、加密光通信和高密度等离子体约束等领域提供重要的应用参考。

This project presents a method of direct generation and high-efficency amplification of a switchable vortex laser based on a liquid-core optical fiber or liquid-core simple photonic crystal fiber Brillouin amplifier. It provides a new feasible approach to obtain a high-energy narrow-pulse vortex laser with orbital angular momentum and porlarization switch. In this project, we investigate the generation of a stable vortex laser with switchable orbital angular momentum and polarization state as well as high-efficiency Brillouin amplification of narrow-pulse swithcable vortex laser. The latter includes the study of the theory of Brillouin amplification of a vortex laser, the generation of narrow-pulse Stokes signal beam and the control of characteristics of amplified vortex laser. We will focus on the the key scientific problems such as the switch of orbital angular momentum and polarization state, the control of spatial and temporal behavior characteristics in the generation and amplification of a vortex laser as well as stability analysis. Thus, high-energy narrow-pulse switchable vortex laser technology will be developed, and the technological difficulties in the tranditional optical fiber technology will be solved. It is expected to achieve a switchable vortex laser with the energy of greater than 1mJ, the pulse width of less than 5ns, and the energy extraction efficiency of larger than 40%. The research results will provide important application reference for laser processing, encryption optical communication, high-density plasma confinement, and so on.