Axially controllable multiple orbital angular momentum beam generator.

In recent years, orbital angular momentum (OAM) beams and their generation methods have drawn increasing interest. Generating multiple OAMs in a three-dimensional space simply and efficiently is meaningful and challenging. Herein, we proposed an integrated multi-OAM generator based on the independent controlling phase division. Realized through the two-photon additive manufacturing, the device possesses a continuous surface with a diameter of 100 μm. Using the generator, arbitrary OAM modes were demonstrated, including the axial position, the number of topological charges, and the direction of rotation. The unique optical characteristics were mutually verified experimentally and through simulation. Vortex beams carrying multiple OAMs will provide more degrees of freedom to manipulate light for exciting applications such as optical communications, micromanipulation, and quantum optics. [ABSTRACT FROM AUTHOR]