Robust measurement of orbital angular momentum of a partially coherent vortex beam under amplitude and phase perturbations
振幅和相位扰动下部分相干涡旋光束轨道角动量的稳健测量
振幅と位相外乱下の部分コヒーレント渦ビーム軌道角運動量のロバストな測定
진폭과 위상 교란 하부 상간 와선 광속 궤도 각동량의 안정적인 측정
Medición robusta del momento angular orbital de un haz de vórtice parcialmente coherente bajo perturbaciones de amplitud y fase
Mesure robuste du moment angulaire orbital du faisceau de Vortex partiellement cohérent sous perturbations d'amplitude et de phase
Устойчивое измерение углового движения на орбите частично когерентного вихревого луча при амплитудных и фазовых возмущениях
Zhao Zhang 张钊 ¹ ², Gaoyuan Li 李高远 ¹, Yonglei Liu 刘永雷 ³, Haiyun Wang 王海云 ⁴, Bernhard J. Hoenders ⁵, Chunhao Liang 梁春豪 ¹ ² ⁶, Yangjian Cai 蔡阳健 ¹ ² ⁶, Jun Zeng 曾军 ¹ ² ⁶
¹ Shandong Provincial Engineering and Technical Center of Light Manipulations & Shandong Provincial Key Laboratory of Optics and Photonic Device, School of Physics and Electronics, Shandong Normal University, Jinan 250358, China
中国 济南 山东师范大学物理与电子科学学院 光学与光子器件技术重点实验室 山东省光场调控工程技术中心
² Collaborative Innovation Center of Light Manipulation and Applications, Shandong Normal University, Jinan 250358, China
中国 济南 山东师范大学 光场调控及应用协同创新中心
³ School of Physical Science and Technology, Soochow University, Suzhou 215006, China
中国 苏州 苏州大学物理科学与技术学院
⁴ School of Physical Science and Technology, Suzhou University of Science and Technology, Suzhou 215009, China
中国苏州 苏州科技大学物理科学与技术学院
⁵ Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, NL-9747 AG Groningen, The Netherlands
⁶ Joint Research Center of Light Manipulation Science and Photonic Integrated Chip of East China Normal University and Shandong Normal University, East China Normal University, Shanghai 200241, China
中国 上海 华东师范大学 华东师范大学和山东师范大学 光场调控科学与光子芯片器件联合研究中心
The ability to overcome the negative effects, induced by obstacles and turbulent atmosphere, is a core challenge of long-distance information transmission, and it is of great significance in free-space optical communication. The spatial-coherence structure, that characterizes partially coherent fields, provides a new degree of freedom for carrying information. However, due to the influence of the complex transmission environment, the spatial-coherence structure is severely damaged during the propagation path, which undoubtedly limits its ability to transmit information.
Here, we realize the robust far-field orbital angular momentum (OAM) transmission and detection by modulating the spatial-coherence structure of a partially coherent vortex beam with the help of the cross-phase. The cross-phase enables the OAM information, quantified by the topological charge, hidden in the spatial-coherence structure can be stably transmitted to the far field and can resist the influence of obstructions and turbulence within the communication link. This is due to the self-reconstruction property of the spatial-coherence structure embedded with the cross-phase.
We demonstrate experimentally that the topological charge information can be recognized well by measuring the spatial-coherence structure in the far field, exhibiting a set of distinct and separated dark rings even under amplitude and phase perturbations. Our findings open a door for robust optical signal transmission through the complex environment and may find application in optical communication through a turbulent atmosphere.
