可调谐DFB激光器泵浦的PPLN绿色倍频光源  

PPLN green frequency doubling light source pumped by tunable DFB laser

作　　者：白思思 阙天行 李京儒 连霜 姜培培[1] BAI Sisi;QUE Tianxing;LI Jingru;LIAN Shuang;JIANG Peipei(School of Ophthalmology&Optometry,Wenzhou Medical University,Wenzhou Zhejiang 325035,China;Equipment Department,Li Huili Hospital of Ningbo Medical Center,Ningbo Zhejiang 315046,China)

机构地区：[1]温州医科大学眼视光学院(生物医学工程学院),浙江温州325035 [2]宁波市医疗中心李惠利医院设备科,浙江宁波315046

出　　处：《激光杂志》2024年第7期42-48,共7页Laser Journal

基　　金：国家自然科学基金青年基金(No.61405174);浙江省自然科学基金(No.LY18F050010)。

摘　　要：为研制脉冲宽度、重复频率以及输出功率可调谐至单光子级别的可见光波段高重频纳秒级窄脉冲光源,提出了一种基于增益调制型DFB激光器和PPLN晶体的绿色倍频光源设计方案。通过自制的纳秒级高速驱动电路以脉冲方式驱动DFB激光器产生固定波长的泵浦源;利用光纤半导体衰减器调节衰减量,调制泵浦光强度;采用PPLN晶体作为非线性晶体材料,通过其可调谐特性得到准相位匹配的绿色倍频激光输出。实验结果表明,DFB激光器输出的泵浦光功率和中心波长稳定,脉冲宽度1.02 ns~10.25 ns、工作频率1 Hz~10 MHz连续独立可调,泵浦光功率衰减至-44.61 dB时工作于532.96 nm波段的绿色倍频光输出脉冲平均光子数约为384 N,倍频光-光转换效率9.3%。To develop a high repetition rate nanosecond narrow-pulse light source with with pulse width,repetition frequency and output power tunable to the single-photon level for the visible wavelength with high repetition frequency,a green frequency-doubling light source design based on a gain-modulated DFB laser and a PPLN crystal is proposed.The DFB laser is driven by a homemade nanosecond high-speed driver circuit in a pulsed mode to generate a fixed-wavelength pump source;using a fiber optic semiconductor attenuator to adjust the attenuation amount and modulate the intensity of pump light;using PPLN crystal as a nonlinear crystal material,a quasi phase matched green frequency doubling laser output was obtained through its tunable properties.The experimental results show that the pump power and center wavelength of the gain modulated DFB laser are stable,with a pulse width of 1.02~10.25 ns and an operating frequency of 1 Hz~10 MHz that can be continuously and independently adjusted.When the power of pump light decays to-44.61 dB,the average photon number of the green frequency doubling light output pulse is about 384N,and the conversion efficiency of the frequency doubling light to light is 9.3%.

关 键 词：纳秒级窄脉冲 增益调制 DFB激光器 绿色倍频激光 光纤半导体衰减器 

分 类 号：TN248[电子电信—物理电子学]