小芯径光子晶体光纤中基于前向受激布里渊散射的超光速传输特性  

Superluminal Propagation Induced by Forward Stimulated Brillouin Scattering in Small-core Photonic Crystal Fibers

作　　者：吴栋明 侯尚林[1] 雷景丽[1] 王道斌[1] 李晓晓[1] WU Dong⁃ming;HOU Shang⁃lin;LEI Jing⁃li;WANG Dao⁃bin;LI Xiao⁃xiao(School of Science,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]兰州理工大学理学院,兰州730050

出　　处：《光子学报》2020年第7期170-177,共8页Acta Photonica Sinica

基　　金：The National Natural Science Foundation of China(No.61665005);the HongLiu First-class Disciplines Development Program of Lanzhou University of Technology.

摘　　要：理论研究了小芯径光子晶体光纤中基于前向受激布里渊散射的快光.利用前向受激布里渊散射三波耦合方程,通过傅里叶变换,计算小芯径光子晶体光纤中的群折射率和增益系数.用有限元法模拟了声场和光场的分布、信号光时间提前量和展宽因子.小芯径光子晶体光纤中光场与声场可以有效地重叠在纤芯中,增强了它们之间的非线性相互作用,导致强的受激布里渊散射和大的时间提前量.随着信号光传输距离的增加,时间提前量成非线性增长,与此同时,信号光被压缩.随着初始脉冲的增大,脉冲展宽因子逐渐趋于平稳.当传输距离为70 m,初始脉冲宽度为200 ns,泵浦功率为600 mW,计算出时间提前量为21.76 ns和脉冲展宽因子为0.77.The forward stimulated Brillouin scattering based fast light in small-core photonic crystal fibers is theoretically investigated.Three-wave coupled wave equations of forward stimulated Brillouin scattering in frequency domain were derived to calculate the group refractive index and gain coefficient in small-core photonic crystal fibers by Fourier transformation,then optical and acoustic field distribution,advancement and broadening factor of signal pulses induced by forward stimulated Brillouin scattering were simulated by the finite element method.Tight confinement of the optical fundamental mode and acoustic modes strengthens nonlinear interaction in the small-core photonic crystal fibers and results in strong SBS and large advancement of time.The time advancement grows nonlinearly with the transmission distance of signal light increasing,and the signal pulses are compressed.The pulse broadening factor gradually levels off with the growth of the initial pulse width.The time advancement of 21.76 ns and pulse broadening factor of 0.77 are evaluated at the transmission distance of 70 m,the initial pulse width of 200 ns and the pumping pulse power of 600 mW.

关 键 词：前向受激布里渊散射 光子晶体光纤 负增益 时间提前量 展宽因子 

分 类 号：TN929.11[电子电信—通信与信息系统]