Generation of dipole vortex array using spiral Dammann zone plates

Abstract

We propose a new diffractive optical element, called a spiral Dammann zone plate (SDZP), to generate a series of dipole vortices along the optical axis in the focal region of a focusing objective. By combining this SDZP and another Dammann grating, we describe the generation of three-dimensional dipole vortex arrays in the focal volume of an objective. For experimental demonstration, a 1×5 SDZP with base charge of l=1 is fabricated by using lithography and wet-etching techniques, and a 1×5 coaxial dipole vortex array is achieved for an objective of NA=0.127. Furthermore, by combining the 1×5 SDZP and another 5×5 Dammann grating, a 5×5×5 dipole vortex array is also experimentally demonstrated. The results show that topological charges of these 5×5 vortex arrays on five coaxial planes could be tunable by selecting a vortex beam carrying different charge as the incident field.

Description of a multifocal arrangement of asymmetric Kummer-beam optical vortices

“…This behavior was experimentally verified using binary VPLs [19]. Binary or discretized phase masks differ from the one proposed by Anzolin et al in that they produce multifocal arrangements with multiple OVs [22,23,25,26]. In particular, Rumi et al [23] show analytically that an on-axis Gaussian beam impinging into a DVPL produces secondary optical vortices (SOVs) at different positions of the optical axis, depending on the topological charge of the principal vortex and the number of discretization levels N .…”

Design and applications of digital diffractive gratings

“…Vortex beam has been well studied [5] with the weak laser intensity for applications of high resolution microscopy, optical tweezers for particle manipulation, lithography, optical communication, etc.. If such a vortex laser beam is focused on the surface of materials, the angular momentum might be transferred into the electrons excited by high-power laser, thereby producing the electrons with angular momentum.…”

Generation of Arbitrary Longitudinal Polarization Vortices by Pupil Function Manipulation

“…[ 21 ] To create multiple optical vortices, the straightforward idea is to use optical gratings, such as vortex gratings [ 22 ] and Damman ones. [ 23,24 ] Although these grating‐based approaches have comparative simple schemes, they suffer from a problem in common that the energy of the incident light is inevitably distributed to the undesired diffraction orders, raising the risk of disturbance to the final field. An alternative solution is to use metasurfaces.…”