对非共线相位匹配LBO晶体飞秒光参变放大器进行了系统地分析和理论研究,用数值方法得出了非共线角、相位匹配角、增益和增益带宽之间的关系,给出了放大器设计的各种最优化参量.研究结果表明,这种参变放大器不仅可以实现较高的参变增益和获得极宽的增益带宽,还具有较大的参变允许角、较小的走离角和小的群速色散,因此这种参变放大器对于以纳秒级高功率激光作为抽运光,利用光参变啁啾脉冲放大(OPCPA)技术高效率参变放大飞秒脉冲产生1012 W甚至1015 W级的超强超短激光脉冲具有重要的意义.建立的理论模型具有普遍意义,也为其他类似的参变过程提供了重要的理论依据.

The characteristic properties of type Ⅰ (e→o+o) nocollinear phase matched LBO (LiB 3O 5) optical parametric chirped pulse amplifier are investigated. A theoretical model of noncollinear phase matched parametric process in LBO is presented. Using the numerical method, the analytical formulation for the parametric efficiency coefficient, effective gain, parametric bandwidth, gain bandwidth of the amplifier are obtained. The numerical simulation results demonstrate that not only the high gain could be obtained in this amplifier, but also the broadest gain spectrum bandwidth could be attained. It provides a great potential to efficiently femto second light pulses to generate new extremes in power, intesity and pulse duration.