激光线宽对单次通过PPMgO：LN晶体倍频效率的影响  

Influence of laser linewidth on the conversion efficiency of single-pass frequency doubling with a PPMgO:LN crystal

作　　者：张孔[1] 白建东[1] 何军[1] 王军民[1] 

机构地区：[1]量子光学与光量子器件国家重点实验室(山西大学),山西大学光电研究所,太原030006

出　　处：《物理学报》2016年第7期178-182,共5页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:61475091,11274213,61205215,61227902);国家重大科学研究计划(批准号:2012CB921601)资助的课题~~

摘　　要：通过单次穿过PPMgO:LN晶体产生了2.06 W的780 nm可调谐的连续倍频光.采用1560 nm的分布反馈式(DFB)半导体激光器、光栅外腔半导体激光器(ECDL)和分布反馈式掺铒光纤激光器(DFB-EDFL)分别作为掺铒光纤放大器(EDFA)的注入光源,所用的EDFA具有保持窄线宽的功能,因此可以忽略它对基波线宽的展宽.研究了激光线宽对单次通过PPMg O:LN晶体的倍频效率的影响.控制三台激光器各自注入EDFA的功率一致,同时也保持EDFA的输出功率.在基波功率为12.42 W时,使用DFB半导体激光器注入EDFA时得到了1.36 W的780 nm倍频光输出,转换效率为11.0%;使用ECDL作为种子源时得到了1.78 W的780 nm倍频光输出,转换效率为14.3%;使用DFB-EDFL作为种子源时得到了2.06 W的780 nm倍频光输出,转换效率为16.6%.测得三台种子激光器的线宽分别为1.2 MHz(DFB),200 k Hz(ECDL)和600 Hz(DFB-EDFL).线宽越窄,倍频效率越高,实验结果与理论分析一致.We report on the generation of 2.06 W of tunable cw light at 780 nm by a single-pass frequency doubling in a PPMg O：LN crystal with a seeded high-power fiber amplifier. A 1560 nm distributed feedback（DFB） diode laser, a Littman-type grating external-cavity diode laser（ECDL） and a DFB-type erbium-doped fiber laser（DFB-EDFL） were separately used as a seeding laser source of an erbium-doped fiber amplifier（EDFA）. Here we use the EDFA which has a narrow linewidth option, the fundamental frequency light will not be obviously broadened. The influence of laser linewidth on the conversion efficiency of frequency doubling is investigated. The injection power and output power of EDFA must be consistent. So when temperature of the PPMg O：LN crystal is fixed, the conversion efficiency for different seeding resources can be obtained as follows. When the fundamental power is 12.42 W, using the DFB as seeding resource yields 1.36 W of 780 nm doubling output, and the corresponding conversion efficiency is 11.0%. Using the ECDL as seeding source yields 1.78 W of 780 nm doubling output, and the corresponding conversion efficiency is 14.3%. While using the DFB-EDFL as seeding source yields 2.06 W of 780 nm doubling output, and the conversion efficiency is 16.6%.The measured laser linewidths of the three seeding sources are 1.2 MHz, 200 k Hz, and 600 Hz for the DFB, ECDL,and DFB-EDFL, respectively. The experimental results show that the narrower laser linewidth, the higher doubling efficiency, and the experimental results agree with our theoretical analysis.

关 键 词：倍频 激光线宽 转换效率 

分 类 号：O734[理学—晶体学]