title: Curved singular beams for three-dimensional particle manipulation.
abstract: For decades, singular beams carrying angular momentum have been a topic of considerable interest. Their intriguing applications are ubiquitous in a variety of fields, ranging from optical manipulation to photon entanglement, and from microscopy and coronagraphy to free-space communications, detection of rotating black holes, and even relativistic electrons and strong-field physics. In most applications, however, singular beams travel naturally along a straight line, expanding during linear propagation or breaking up in nonlinear media. Here, we design and demonstrate diffraction-resisting singular beams that travel along arbitrary trajectories in space. These curved beams not only maintain an invariant dark "hole" in the center but also preserve their angular momentum, exhibiting combined features of optical vortex, Bessel, and Airy beams. Furthermore, we observe three-dimensional spiraling of microparticles driven by such fine-shaped dynamical beams. Our findings may open up new avenues for shaped light in various applications.
authors.affiliation: 1] The MOE Key Laboratory of Weak-Light Nonlinear Photonics, and TEDA Applied Physics Institute and School of Physics, Nankai University, Tianjin 300457, China [2] CREOL/College of Optics, University of Central Florida, Orlando, Florida 32816 [3] Department of Physics and Astronomy, San Francisco State University, San Francisco, CA 94132 [4] Science and Technology on Solid-State Laser Laboratory, North China Institute of Electronics Optics, Beijing 100015, China.
authors.forename: Juanying
authors.initials: J
authors.lastname: Zhao
authors.affiliation: 1] Department of Mathematics and Applied Mathematics, University of Crete, Heraklion 71409, Greece [2] Max Planck Institute for the Science of Light, Erlangen D-91058, Germany.
authors.forename: Ioannis D
authors.initials: ID
authors.lastname: Chremmos
authors.affiliation: The MOE Key Laboratory of Weak-Light Nonlinear Photonics, and TEDA Applied Physics Institute and School of Physics, Nankai University, Tianjin 300457, China.
authors.forename: Daohong
authors.initials: D
authors.lastname: Song
authors.affiliation: CREOL/College of Optics, University of Central Florida, Orlando, Florida 32816.
authors.forename: Demetrios N
authors.initials: DN
authors.lastname: Christodoulides
authors.affiliation: Department of Mathematics and Applied Mathematics, University of Crete, Heraklion 71409, Greece.
authors.forename: Nikolaos K
authors.initials: NK
authors.lastname: Efremidis
authors.affiliation: 1] The MOE Key Laboratory of Weak-Light Nonlinear Photonics, and TEDA Applied Physics Institute and School of Physics, Nankai University, Tianjin 300457, China [2] Department of Physics and Astronomy, San Francisco State University, San Francisco, CA 94132.
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Chen