In recent years,orbital angular momentum(OAM),as a new usable degree of freedom of photons,has been widely applied in both classical optics and quantum optics.For example,digital spiral imaging uses the OAM spectrum o...In recent years,orbital angular momentum(OAM),as a new usable degree of freedom of photons,has been widely applied in both classical optics and quantum optics.For example,digital spiral imaging uses the OAM spectrum of the output beam from the object to restore the symmetry information of the object.However,the related experiments have been carried out in free space so far.Due to the poor anti-noise performance,limited transmission distance and other reasons,the practicability is seriously restricted.Here,we have carried out a digital spiral imaging experiment through a few-mode fiber,to achieve the identification of the symmetry of object by measuring the OAM spectrum of the output beam.In experiment,we have demonstrated the identification of the symmetry of amplitude-only and phase-only objects with the two-,three-and four-fold rotational symmetries.We also give the understanding of the physics.We believe that our work has greatly improved the practical application of digital spiral imaging in remote sensing.展开更多
基金Supported by the National Key R&D Program of China under Grant Nos 2017YFA0303800 and 2017YFA0303700the National Natural Science Foundation of China under Grant Nos 11534006,11674184,11774183 and 11804187+1 种基金the Natural Science Foundation of Tianjin under Grant No 16JCZDJC31300the Collaborative Innovation Center of Extreme Optics
文摘In recent years,orbital angular momentum(OAM),as a new usable degree of freedom of photons,has been widely applied in both classical optics and quantum optics.For example,digital spiral imaging uses the OAM spectrum of the output beam from the object to restore the symmetry information of the object.However,the related experiments have been carried out in free space so far.Due to the poor anti-noise performance,limited transmission distance and other reasons,the practicability is seriously restricted.Here,we have carried out a digital spiral imaging experiment through a few-mode fiber,to achieve the identification of the symmetry of object by measuring the OAM spectrum of the output beam.In experiment,we have demonstrated the identification of the symmetry of amplitude-only and phase-only objects with the two-,three-and four-fold rotational symmetries.We also give the understanding of the physics.We believe that our work has greatly improved the practical application of digital spiral imaging in remote sensing.