基于双壁碳纳米管低阈值1895nm锁模激光器

Low Threshold 1895nm Mode-Locked Laser Based on Double Wall Carbon Nanotubes

结合特殊设计的低阈值五镜折叠腔,利用垂直生长法自制的双壁碳纳米管,并将其作为可饱和吸收体在Tm,Ho…LLF激光器中实现了连续锁模运转。在连续激光运转下,吸收抽运阈值低至59 mW,光-光转化效率为30.09%。在腔内插入饱和吸收体后,吸收抽运阈值提高至107mW。当吸收抽运功率大于1562mW时,激光运转进入稳定的连续锁模状态,对应锁模脉冲的重复频率为100 MHz,脉冲宽度约为515ps;当吸收抽运功率达到2 W时,最高输出功率为234mW,中心波长为1895nm,对应最大单脉冲能量为2.34nJ。

We combine the specially designed low threshold five-mirror folded cavity,employ the home-made double wall carbon nanotubes（DWCN）as saturable absorber by vertical growth method,and realize continuous mode locking operation in Tm,HoLLF all solid state laser.Absorbed pump threshold is as low as 59 mW under the continuous-wave laser operation,and the light to light conversion efficiency reaches 30.09%.The absorbed pump threshold is increased to 107 mW after DWCN is inserted in the cavity.When the absorbed pump power is higher than 1562 mW,the laser operation gets into a stable continuous mode-locked state,for which the corresponding mode-locked pulse repetition frequency is 100 MHz,and the pulse width is about 515 ps.When absorbed pump power reaches 2 W,the maximum output power is 234 mW,the central wavelength is 1895 nm,and the maximum single pulse energy is 2.34 nJ.