Excitation of high order orbital angular momentum modes in ultra-short chiral long period fiber gratings
Zheng Huang, Zhiyong Bai, Guoxuan Zhu, Churou Huang, Jiayan Chen, Shen Liu, Cailing Fu, Jun He, Yiping Wang
Abstract
A class of ultra-short chiral long period fiber gratings (CLPFGs) are prepared by writing a spiral curve on the surface of a six-mode fiber. The CLPFGs are applied to excite ±2 nd - and ±3 rd -order orbital angular momentum (OAM) modes. The coupling efficiency of the CLPFG in these modes can be as high as 99%, when the length is only 0.5cm. The polarization characteristic of the excited higher-order OAM modes in CLPFGs was theoretically analyzed and experimentally investigated. Results show that the obtained ±2 nd - and ±3 rd -order OAM modes are polarization independent, as expected.
Topics & Concepts
OpticsAngular momentumPolarization (electrochemistry)PhysicsExcitationExcited stateMode volumeLong-period fiber gratingOptical fiberPolarization-maintaining optical fiberMaterials scienceAtomic physicsFiber optic sensorClassical mechanicsQuantum mechanicsChemistryPhysical chemistryOrbital Angular Momentum in OpticsPlasmonic and Surface Plasmon ResearchAdvanced Fiber Laser Technologies