Time-Resolved Femtosecond Degenerate Four-Wave Mixing in LiNbO3:Fe,Mg Crystal
WANG Zhen-Hua1,2, ZHANG Xin-Zheng1,2, XU Jing-Jun1,2, WU Qiang1,2, QIAO Hai-Jun1,2, TANG Bai-Quan1,2, RUPP Romano3, KONG Yong-Fa4, CHEN Shao-Lin4, HUANG Zi-Heng4, LI Bing4, LIU Shi-Guo4, ZHANG Ling4
1Photonics Research Center, Institute of Physical Science, Nankai University, Tianjin 300071
2Ultrafast Photonics Laboratory, Teda Applied Physics School, Nankai University, Tianjin 300457
3Institute of Experimental Physics, Vienna University, A-1090 Wien, Austria
4R&D Center for Photon-Electro Materials, Nankai University, Tianjin 300071
Time-Resolved Femtosecond Degenerate Four-Wave Mixing in LiNbO3:Fe,Mg Crystal
1Photonics Research Center, Institute of Physical Science, Nankai University, Tianjin 300071
2Ultrafast Photonics Laboratory, Teda Applied Physics School, Nankai University, Tianjin 300457
3Institute of Experimental Physics, Vienna University, A-1090 Wien, Austria
4R&D Center for Photon-Electro Materials, Nankai University, Tianjin 300071
Abstract： Forward degenerate four-wave mixing (DFWM) processes are investigated with a femtosecond pulsed laser in lithium niobate crystal doubly-doped with magnesium and iron (LiNbO3:Fe,Mg). The pulse energy dependence reveals a pure third-order nonlinear response, and the third-order nonlinear susceptibility x(3) in the material is evaluated to be 4.96×10-13esu. The time-resolved DFWM process shows a response time of x(3) shorter than 100fs, which is due to the nonresonant electronic nonlinearities. Our results indicate that LiNbO3 crystals have potentials for ultrafast real-time optical processing systems, which require a large and fast x(3) optical nonlinearity.
2005, Vol. 22 
