CAJ | 학술논문

飞秒光学频率梳波长覆盖范围向可见光波长扩展对于碘稳频激光的绝对频率测量以及光钟研究中钟激光的绝对频率测量都具有十分重要的意义.本文在自行研制掺Er光纤飞秒光学频率梳的基础上,采用放大-倍频-扩谱的方案,实现了激光输出波长向可见光波长的扩展.掺Er光纤飞秒光学频率梳输出的一部分光激光脉冲,功率约为8 mW,首先经掺Er光纤放大器将功率提高到531 mW,此后利用MgO： PPLN晶体倍频,倍频后激光的功率为170 mW,倍频效率为32%,脉冲宽度为85 fs.倍频后的激光通过光子晶体光纤进行光谱展宽.通过优化入射光偏振状态可以实现波长覆盖500—1000 nm,输出功率为85 mW,耦合效率为50%.采用小型化碘稳频532 nm Nd： YAG激光器输出激光与光学频率梳光谱展宽后的激光进行拍频可以获得30 dB的拍频信号.覆盖可见光波长的掺Er光纤飞秒光学频率梳为可见光范围内激光的绝对频率测量提供了技术手段.
비초광학빈솔소파장복개범위향가견광파장확전대우전은빈격광적절대빈솔측량이급광종연구중종격광적절대빈솔측량도구유십분중요적의의.본문재자행연제참Er광섬비초광학빈솔소적기출상,채용방대-배빈-확보적방안,실현료격광수출파장향가견광파장적확전.참Er광섬비초광학빈솔소수출적일부분광격광맥충,공솔약위8 mW,수선경참Er광섬방대기장공솔제고도531 mW,차후이용MgO： PPLN정체배빈,배빈후격광적공솔위170 mW,배빈효솔위32%,맥충관도위85 fs.배빈후적격광통과광자정체광섬진행광보전관.통과우화입사광편진상태가이실현파장복개500—1000 nm,수출공솔위85 mW,우합효솔위50%.채용소형화전은빈532 nm Nd： YAG격광기수출격광여광학빈솔소광보전관후적격광진행박빈가이획득30 dB적박빈신호.복개가견광파장적참Er광섬비초광학빈솔소위가견광범위내격광적절대빈솔측량제공료기술수단.
Femtosecond optical frequency combs (FOFCs) with output wavelengths covering visible light have potential ap-plications in absolute frequency measurement of iodine-stabilized lasers and optical clock lasers. Based on optical amplification, frequency doubling and spectrum broadening, a home-made Er-fiber femtosecond optical frequency comb (Er-FOFC) with output wavelengths covering visible light is demonstrated. One path with an average power of 8 mW from Er-FOFC is used as the seed pulse for spectrum broadening to cover the visible light. This path is first amplified to 532 mW by injecting into an Er-doped femtosecond fiber amplifier with combined forward and backward pumping and then frequency doubled with a MgO:PPLN crystal with an output power of 85 mW, frequency-doubling e?ciency of 32%and pulse duration of 85fs. The output power of this path can be first amplified to 532 mW through an Er-doped fem-tosecond fiber amplifier when the forward pumping and backward pumping both turn on. Then the frequency-doubling laser can be generated in a MgO: PPLN crystal. The frequency-doubling e?ciency is 32% and the pulse duration is 85 fs;the frequency-doubling light is spectrally broadened from 500 to 1000 nm in a photonic crystal fiber (PCF), with an output power of 85 mW and coupling e?ciency of 50%. To verify the performance of the broadened spectrum, the light from the Er-FOFC and a compact iodine-stabilized frequency-doubled Nd: YAG laser at 532 nm is beaten. A beat signal with a signal-to-noise ratio of 30 dB at 100 kHz RBW is obtained, which provides a useful tool for absolute frequency measurement of visible lasers.