宽带钕玻璃激光的高效三次谐波转换

High efficiency third-harmonic generation of broadband Nd:glass laser

提出了一种新颖的宽频带钕玻璃激光三倍频技术———组合激光工作模式(宽带激光与窄带激光混频)方案。数值模拟研究表明:利用窄线宽钕玻璃激光脉冲,可以缓解宽频带激光谐波转换过程中群速度失配对转换效率的影响,从而提高宽带钕玻璃激光的转换效率;并且该方案可以与目前使用成熟的双和频晶体方案结合,从而能支持目前钕玻璃激光装置能达到的最大带宽约5nm的高效三倍频(理论上效率达约80%)。

The paper proposes and numerically demonstrates a simple and efficient broadband frequency-tripling scheme for Nd：glass laser system based on mixing narrowband and broadband laser pulses in the sum-frequency generation（SFG） process.The group-velocity mismatching effect in the of SFG process is substantially alleviated with the assist of a narrowband laser,which is the dominant obstacle to efficient broadband third-harmonic generation.Moreover,by adding a second tripler in the SFG process,the proposed scheme will support efficient frequency tripling over a bandwidth of 5 nm（theoretical efficiency more than 80%）.