Modern society relies heavily on encoding information for efficient transmission. One of the most common methods is sending data as pulses of laser light through optic cables, which power the internet and telecommunications. But as demand for data transfer grows, so does the need to find more effective and higher-capacity methods to transmit this information.
In a significant breakthrough, researchers at Aalto University in Finland have developed a new technique for creating what scientists call “vortices”—tiny hurricanes of light that can carry information. These light vortices, produced by controlling metallic nanoparticles, represent a potential leap forward in data encoding and transmission. The Aalto team, led by Doctoral Researchers Kristian Arjas and Jani Taskinen under Professor Päivi Törmä, introduced a novel approach using quasicrystal-inspired designs to create and control these light vortices. The development not only advances fundamental physics but also offers a potential new method for transmitting information that could increase data capacity in optical systems.
A light vortex is a unique structure resembling a hurricane. Like the calm eye of a hurricane, the center of the vortex is dark, surrounded by a bright ring of light. This effect occurs because the light’s electric field around the center points in different directions, canceling out at the center and leaving it dark. Previous research established that the number and complexity of vortices that can form depends on the symmetry of the structure that generates them. For instance, a single vortex can be created using particles arranged in a square shape, while hexagonal arrangements produce double vortices, and increasingly complex shapes require more intricate arrangements. This limitation had previously made it difficult to produce a full range of vortex types.
However, the team at Aalto developed a method for creating structures that support a wider variety of vortices than previously thought possible. Their approach is based on using geometric shapes in a class known as quasicrystals, which exhibit patterns halfway between strict order and randomness. According to Professor Törmä, this research focuses on the relationship between symmetry and vortex rotation, examining what kinds of light vortices can be generated with different patterns. This quasicrystal design is neither fully regular nor chaotic, allowing for more versatile manipulation of light vortices.
The researchers achieved this breakthrough by arranging 100,000 metallic nanoparticles—each about one-hundredth the diameter of a human hair—in a specific configuration. They discovered that by placing these nanoparticles in areas of the electric field that experience minimal interaction (the “dead spots”), they could enhance the field’s desired properties and suppress unwanted effects. By doing so, they created a unique design that isolates particular field characteristics, making it suitable for creating complex light vortices. Doctoral researcher Taskinen explains that electric fields have areas of high vibration and other areas where there is almost no activity. By positioning particles in these inactive zones, they were able to selectively enhance the fields that had the most useful qualities for applications, such as data transmission.
The implications of this discovery are far-reaching, particularly for fields requiring high-capacity data transmission, such as telecommunications. According to Arjas, this technique could eventually enable the transmission of data through optical fiber at rates eight to sixteen times higher than current capabilities. By encoding information into these light vortices and sending them down optical cables, much more data could be stored and transmitted in a smaller space. Upon reaching their destination, the vortices could then be “unpacked,” yielding a greater quantity of information than current methods allow.
While this discovery is still in its early stages, the research opens up new avenues in the growing field of topological light studies. Although it may take years to translate this technique into practical technology, it has the potential to transform data transmission in areas requiring highly compact and efficient information delivery. The researchers are optimistic about future advancements, but note that practical applications and scaling the design will require substantial engineering efforts.
In addition to this project, the Quantum Dynamics group at Aalto University is also involved in related research areas, including superconductivity and organic LED improvements. Their work utilizes OtaNano, a research facility dedicated to nano-, micro-, and quantum technology, providing the team with the advanced tools needed to push the boundaries of quantum dynamics and applied physics. This breakthrough at Aalto University represents not only a fundamental advancement in understanding light vortices but also a promising step toward more efficient and powerful data transmission methods that could eventually become foundational to telecommunications and computing.
The study is published in the journal Nature Communications.