轨道角动量模式在柚子型微结构光纤中的传输  

Transmission of Orbital Angular Momentum Modes in Grapefruit-Type Microstructure Fiber

作　　者：乔文[1,2] 高社成[1,2] 雷霆[1,2] 吉虹[3] 阮银兰[3] 谢振威[1,2] 杨传武[1,2] 袁小聪[1,2] 

机构地区：[1]深圳大学纳米光子学研究中心,广东深圳518060 [2]深圳大学光电工程学院光电子器件与系统教育部/广东省重点实验室,广东深圳518060 [3]阿德莱德大学光子和先进传感器研究所

出　　处：《中国激光》2017年第4期184-189,共6页Chinese Journal of Lasers

基　　金：国家自然科学基金(61138003;61427819;61405121);深圳大学引进人才科研启动项目(000011;000075)

摘　　要：研究了轨道角动量(OAM)模式在柚子型微结构光纤(MOF)中的传输。光纤纤芯周围存在一层直径为3μm的柚子型空气孔,由于空气孔与光纤纤芯之间存在较大的折射率差,传输的光被局限在纤芯中,从而形成稳定的传输模式。通过有限元法对光纤中的矢量本征模式进行模拟,得到了模式的有效折射率和模场分布。结果表明,MOF在630nm波长附近可支持10个OAM模式传输,各模式间的有效折射率差达到0.01以上,较大的有效折射率差可抑制光纤中各模式间的相互耦合,从而提高OAM模式在光纤中的传输性能。实验中利用特殊设计的光学旋涡达曼光栅对在光纤中传输1m的OAM_(1,1)和OAM_(-1,1)模式进行解调。The transmission of orbital angular momentum （OAM） modes in grapefruit-type microstructure fiber （MOF）is studied. The fiber core is surrounded by grapefruit-type air holes with diameter of 3 μm. The refractive index difference between fiber core and air hole is large, so that the transmission light can be concentrated into the core and stable modes can be formed. Based on the finite element method, vector eigenmodes in the fiber are analyzed. The effective refractive indexes and the mode filed distributions of these modes are obtained. The results show that the transmission of ten OAM modes can be supported around the wavelength of 630 nm. The effective refractive index differences among OAM modes are larger than 0.01. The large effective refractive index difference can suppress mutual coupling among different modes, and improve the transmission performance of OAM modes in fiber. In addition, we use the special designed optical vortex Dammann gratings in experiments to detect the OAM1.1 and OAM-1,1 modes after transmitting for 1 m in MOF.

关 键 词：光纤光学 轨道角动量 有限元法 柚子型微结构光纤 有效折射率差 模式传输 

分 类 号：TN929.11[电子电信—通信与信息系统]