title: Structured caustic vector vortex optical field: manipulating optical angular momentum flux and polarization rotation.
abstract: A caustic vector vortex optical field is experimentally generated and demonstrated by a caustic-based approach. The desired caustic with arbitrary acceleration trajectories, as well as the structured states of polarization (SoP) and vortex orders located in different positions in the field cross-section, is generated by imposing the corresponding spatial phase function in a vector vortex optical field. Our study reveals that different spin and orbital angular momentum flux distributions (including opposite directions) in different positions in the cross-section of a caustic vector vortex optical field can be dynamically managed during propagation by intentionally choosing the initial polarization and vortex topological charges, as a result of the modulation of the caustic phase. We find that the SoP in the field cross-section rotates during propagation due to the existence of the vortex. The unique structured feature of the caustic vector vortex optical field opens the possibility of multi-manipulation of optical angular momentum fluxes and SoP, leading to more complex manipulation of the optical field scenarios. Thus this approach further expands the functionality of an optical system.
authors.affiliation: Department of Physics, Zhejiang Sci-Tech University, Hangzhou, 310018, China.
authors.forename: Rui-Pin
authors.initials: RP
authors.lastname: Chen
authors.affiliation: National Laboratory of Solid State Microstructures and School of Physics, Nanjing University, Nanjing 210093, China.
authors.forename: Zhaozhong
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia.
authors.forename: Khian-Hooi
authors.initials: KH
authors.lastname: Chew
authors.affiliation: Department of Physics, Zhejiang Sci-Tech University, Hangzhou, 310018, China.
authors.forename: Pei-Gang
authors.initials: PG
authors.lastname: Li
authors.affiliation: National Laboratory of Solid State Microstructures and School of Physics, Nanjing University, Nanjing 210093, China.
authors.forename: Zhongliang
authors.initials: Z
authors.lastname: Yu
authors.affiliation: National Laboratory of Solid State Microstructures and School of Physics, Nanjing University, Nanjing 210093, China.
authors.forename: Jianping
authors.initials: J
authors.lastname: Ding
authors.affiliation: Centre for Optical and Electromagnetic Research, Zhejiang University; Joint Research Center of Photonics of the Royal Institute of Technology (Sweden) and Zhejiang University (China).
authors.forename: Sailing
authors.initials: S
authors.lastname: He