Universal orbital angular momentum spectrum analyzer for beams

Abstract

The orbital angular momentum (OAM) of beams provides a new dimension, and have already found lots of applications in various domains. Among such applications, the precisely and quantitatively diagnostic of intensity distributions among different OAM modes, namely the OAM spectrum of a beam, is of great significance. In this paper we propose and experimentally validate a simple interferential method to achieve this goal. By analyzing the interference pattern formed by the beam and a reference field, the OAM spectrum can be obtained instantaneously. Furthermore, the proposed method is also available for more complex light fields, for instance, the multi-ring optical vortices. In the proof-ofconcept experiment, the OAM spectra of both single-mode and N-fold multiplexed OAM modes with various intensity distributions are well detected. Our work offers a new way to precisely measure the OAM spectra of beams and will advance the development of many applications ranging from classical to quantum physics as the OAM based large-capacity data transmissions, rotation detection, quantum manipulation and so on.

Multiplexed Generation of Generalized Vortex Beams with On‐Demand Intensity Profiles Based on Metasurfaces

“…A GVB can be considered as superposition of a number of simple vortex beams of different topological charges. Here we determine the ranges and the OAM spectrum distributions [ 34 ] of the GVBs. We employ two different approaches to analyze the OAM spectrum of GVB.…”

Spatial-Light-Modulator-Based Multichannel Data Transmission by Vortex Beams of Various Orders

“…where m is an integer value of a topological charge (TC). The convenience of OVs lies in the independence of the field radius, which provides versatility [22][23][24]42] and significant tolerances for aligning the optical system [17,18].…”

Orbital‐Angular‐Momentum‐Encrypted Holography Based on Coding Information Metasurface

“…Metasurfaces can reduce the size of structures and improve the resolution compared to conventional holograms. [ 30–32 ] In the meantime, orbital angular momentum (OAM) carrying spiral‐like phase ( e jlϕ , where l and ϕ represent the helical mode index and the azimuthal angle, respectively) [ 33–39 ] has attracted tremendous attention, because a great number of mutually orthogonal helical mode indices presents the advantages of high information capacity and high security. Hence, OAM provides a new degree of spatial freedom for the EM‐wave manipulation and the spatial domain resource, which can be utilized as the carrier of information.…”