Efficient idler broadening via oppositely dual-chirped difference frequency generation  

作　　者：Haizhe Zhong Bin Hu Saisai Hu Shengying Dai Ying Li Dianyuan Fan 

机构地区：[1]International Collaborative Laboratory of 2D Materials for Optoelectronic Science&Technology of Ministry of Education,Engineering Technology Research Center for 2D Material Information Function Devices and Systems of Guangdong Province,Shenzhen University,Shenzhen 518060,China

出　　处：《High Power Laser Science and Engineering》2020年第2期177-184,共8页高功率激光科学与工程（英文版）

基　　金：This work was supported in part by the National Natural Science Foundation of China(No.61505113);Natural Science Foundation of Guangdong Province(No.2020A1515010541);Science and Technology Project of Shenzhen(Nos.JCYJ20180305124930169,JCYJ20190808143419622 and ZDSYS201707271014468).

摘　　要：Dual-chirped difference frequency generation(DFG)is an advantageous technique for generating the broadband midinfrared(IR)idler wave,which is inaccessible by a population-inversion-based laser system.In principle,the generated idler wave may even suffer a spectrum broadening compared with the driving pulsed lasers if the pump and signal waves are oppositely chirped.However,broadband phase-matching is always the determining factor for the resulting efficiency and the bandwidth of the generated idler wave.In this study,specific to an oppositely dual-chirped DFG scheme,we derive the precondition to realize broadband frequency conversion,wherein a negative(1/υp-1/υi)/(1/υs-1/υi),in terms of the correlation coefficient of the group velocity(σ),is necessary.However,most birefringence bulk crystals can only provide the required material dispersions in limited spectral regions.We show that the periodically poled lithium niobate crystal that satisfies an inactive Type-II(eo-o)quasi-phase-matching condition has a stable negativeσand exerts the expected broadband gain characteristic across an ultra-broad idler spectral region(1.7-4.0µm).Finally,we propose and numerically verify a promising DFG configuration to construct a tunable mid-IR spectrum broader based on the broadband phase-matched oppositely dual-chirped DFG scheme.

关 键 词：MID-INFRARED optical parametric amplification periodically poled lithium niobate crystal ultrafast laser 

分 类 号：TN248[电子电信—物理电子学]