A research group, including Associate Professor Yoshiki Nakata of the Institute of Laser Engineering at the University of Osaka, Noriaki Miyanaga (Professor Emeritus at the University of Osaka) of the Institute for Laser Technology, and Master's Students Yuki Kosaka and Masataka Yoshida (both at the Graduate School of Engineering, the University of Osaka, at the time of the study), has successfully generated a large-scale optical vortex array (mega-optical vortex) consisting of 3,070 simultaneously aligned optical vortices with a high output at the megawatt level. This presents a foundational technology that will enable light control in previously unreachable domains and the exploration of unknown phenomena across a wide range of fields, including quantum technology, life sciences, and photonics. The results were published in Light: Science & Applications.
A. Overall experimental setup. The laser beam is divided into multiple beams using a diffractive optical element (DOE) and recombined through a spiral phase plate (SPP) and a 4f Fourier optical system to form the vortex array.
B. Conceptual illustration of vortex-array formation via multibeam interference.
C. Schematic representation of phase control using the spiral phase plate (SPP).
©CC BY, Reuse permitted with appropriate credit., Yoshiki Nakata et al., The University of Osaka
An optical vortex, in which the wavefront of light travels in a spiral, is attracting attention primarily in the fields of quantum technology and photonics as a special type of light possessing rotational properties (orbital angular momentum). Using optical vortices makes it possible to observe and create new phenomena that were impossible with conventional light.
With conventional generation technologies, there were constraints on the number that could be created simultaneously and the output that could be handled. Both scaling up and increasing output were difficult challenges, and achieving both simultaneously was considered extremely difficult.
The research group reconstructed the optical mode theory that describes optical vortices and combined it with multi-beam interference technology to fundamentally re-examine conventional constraints.
They developed a method to generate a large number of high-output optical vortices by combining existing optical elements, such as a diffractive optical element and spiral phase plate, without the need for special materials or complex controls.
As a result, they succeeded for the first time in the world in generating a large-scale optical vortex array with 3,070 simultaneously aligned optical vortices at a megawatt-level high output.
The generated optical vortices were observed directly, and it was confirmed that each optical vortex possessed a clear singularity structure. Through this method, they experimentally demonstrated that scaling up and high output can be realized at the same time.
The greatest feature of this research lies in its "massively parallel" nature, capable of handling thousands of optical vortices simultaneously at high power. This allows for the simultaneous excitation and control of numerous spatial points, enabling the spatial parallelization of light control that previously could only be achieved sequentially. In fact, the formation of chiral nanostructures was confirmed using the megawatt-level optical vortex array, demonstrating that the optical vortex structure functions effectively even under high-output conditions.
This achievement presents a scalable light control foundation based on interference. It is applicable not only to massively parallel laser processing but also to research in broadband chiral photonics and orbital angular momentum transfer under high-intensity light fields.
Nakata commented, "Until now, the generation of optical vortices, where the wavefront of light travels in a spiral, was limited to a small number at low output. In this study, by re-examining the basic properties of optical vortices from a theoretical perspective, we demonstrated that the two difficult challenges of scaling up and increasing output can be overcome simultaneously. Through the observation and creation of new phenomena, we hope to approach unknown phenomena that were previously unreachable and open up new possibilities for science."
Journal Information
Publication: Light: Science & Applications
Title: Scalable optical vortex arrays enabled by the decomposition of Laguerre-Gaussian beams into three Hermite-Gaussian modes and multibeam interference
DOI: 10.1038/s41377-026-02254-0
This article has been translated by JST with permission from The Science News Ltd. (https://sci-news.co.jp/). Unauthorized reproduction of the article and photographs is prohibited.