Ultrabroadband nonlinear Raman-Nath diffraction against femtosecond pulse laser

作     者：Lihong Hong Baoqin Chen Chenyang Hu Zhi-Yuan Li LIHONG HONG;BAOQIN CHEN;CHENYANG HU;ZHI-YUAN LI

作者机构：School of Physics and OptoelectronicsSouth China University of TechnologyGuangzhou 510641China Guangdong Jingqi Laser Technology Corporation LimitedDongguan 523808China 

出 版 物：《Photonics Research》 (光子学研究（英文版）)

年 卷 期：2022年第10卷第4期

页      面：905-912页

核心收录：

学科分类：080901[工学-物理电子学] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 080401[工学-精密仪器及机械] 0804[工学-仪器科学与技术] 0803[工学-光学工程] 

基　　金：National Natural Science Foundation of China(11974119) Science and Technology Project of Guangdong(2020B010190001) Guangdong Innovative and Entrepreneurial Research Team Program(2016ZT06C594) National Key Research and Development Program of China(2018YFA0306200) Natural Science Foundation of Guangdong Province of China(2019A1515011605) 

主　　题：nonlinear diffraction matching 

摘      要：Nonlinear Raman–Nath diffraction(NRND) offers an effective way to realize multiple noncollinear parametric processes based on the partially satisfied transverse phase-matching conditions in quadratic nonlinear ***, the realization of ultrabroadband NRND(UB-NRND) driven by a high-peak-power ultrashort femtosecond pump laser in two types of nonlinear crystals is reported: periodically poled lithium niobate(PPLN) and chirped PPLN(CPPLN). Multi-order ultrabroadband Raman–Nath second-harmonic(SH) signal outputs along fixed diffraction angles are simultaneously observed. This distinguished transversely phase-matched supercontinuum phenomenon is attributed to the synergic action of natural broad bandwidth of an ultrashort femtosecond pump laser and the third-order nonlinear effect induced spectral broadening, in combination with the principal ultrabroadband noncollinear second-harmonic generation processes. The NRND process with multiple quasiphase matching(QPM) interactions from CPPLN leads to the SH output covering a wide range of wavelengths between 389 and 997 nm and exhibiting an energy conversion efficiency several orders of magnitude higher than previous studies. This UB-NRND scheme would bring better techniques and tools for applications ranging from ultrashort pulse characterization and nondestructive identification of domain structures to accurate parameter monitoring of second-and third-order nonlinear susceptibilities within solid-state nonlinear microstructured materials.