Devi Kavita, Kumar S Chaitanya, Ebrahim-Zadeh M
ICFO-Institut de Ciencies Fotoniques, Mediterranean Technology Park, Barcelona, Spain.
Opt Express. 2011 Jun 6;19(12):11631-7. doi: 10.1364/OE.19.011631.
We report an efficient fiber-laser-based source of high-power, continuous-wave (cw), linearly-polarized radiation at 970 nm in a simple, compact, and practical design. Using direct single-pass second-harmonic-generation (SP-SHG) of a cw thulium fiber laser at 1940 nm in a 40-mm-long periodically-poled LiNbO3 (PPLN) crystal, we have generated 13.1 W of output power at 970 nm for a fundamental power of 40 W at a conversion efficiency as high as 32.7%. The generated second-harmonic output exhibits a passive power stability better than 1.4% (1σ value) over 1 hour, has a linewidth better than 0.3 nm, and a TEM(00) spatial beam profile with M(2)<1.6. Relevant theoretical calculations for the characterization of SP-SHG in the crystal have also been performed.
我们报道了一种基于光纤激光器的高效光源，它采用简单、紧凑且实用的设计，可产生波长为970 nm的高功率连续波（cw）线偏振辐射。通过在40 mm长的周期极化铌酸锂（PPLN）晶体中对1940 nm的连续波铥光纤激光器进行直接单通二次谐波产生（SP - SHG），在40 W的基频功率下，我们在970 nm处产生了13.1 W的输出功率，转换效率高达32.7%。所产生的二次谐波输出在1小时内表现出优于1.4%（1σ值）的无源功率稳定性，线宽优于0.3 nm，且具有TEM(00)空间光束分布，M(2)<1.6。还对晶体中SP - SHG特性进行了相关理论计算。
