kJ级宽带低相干激光驱动装置

kJ low-coherence broadband Nd:glass laser driver facility

激光等离子体相互作用的不稳定性将有望通过降低高功率激光装置输出光束的相干性得到大幅缓解。利用低相干光源作为种子源,采用钕玻璃放大介质,研制成功国际首台kJ级大带宽低相干激光装置,实现了带宽13 nm、能量960 J、脉宽3~10 ns可调,相干时间仅为300 fs的大能量光脉冲输出。输出脉冲光谱匀滑无纵模结构,且谱相位随机分布,可实现脉冲波形和光谱分布的无关联精密调控。该装置不仅成功演示验证了低相干激光驱动器的单元技术及系统集成技术,同时也为激光等离子体相互作用及高能量密度物理研究提供了全新的实验研究平台。

The instability of the laser plasma interaction is expected to be greatly suppressed by reducing the coherence of the output pulse of the high-power laser facilities.Using the low-coherence light as the seed source and the Nd:glass as the amplifying medium,the first kJ low-coherence broadband laser was developed delivering 960 J pulses centered at 1056 nm with a bandwidth of 13 nm.The output pulse has a coherence time of 300 fs and a pulse duration adjustable from 3 ns to 10 ns.The spectrum of laser pulse is smooth with no longitudinal mode structure.And the spectral phase is randomly distributed,which can realize uncorrelated tunable output of pulse waveform and spectral shape.This facility successfully demonstrates the unit and system integration technologies of the broadband low-coherence laser driver and provides a new experimental platform for laser plasma interaction and high energy density physics research.