Light emission from nanostructures, demonstrated for the first time using 3D printing processes

Dr. Jaeyeon Pyo’s team at the Korea Electrotechnology Research Institute (KERI) is the first team in the world to demonstrate light emission patterns from 3D-printed nanowires.

The resolution of display devices is determined by the number of pixels, and the higher the pixel density, the more precise and detailed films and images are displayed. Current research aims to reduce the size of light-emitting devices from the micrometer to the nanometer scale. When the size of these devices shrinks to hundreds of nanometers, the interactions between light and matter change significantly, resulting in different emission patterns. Understanding this light emission from nanostructures is crucial for the practical application of nanoscale light-emitting devices.

The KERI team, which has been working for years on research into nanophotonic 3D printing technologies, has now demonstrated highly directional light emission patterns from 3D-printed nanowires. Conventional chemical or physical vapor deposition methods have difficulty producing light-emitting materials uniformly in desired sizes at specific locations. However, KERI’s 3D printing technology enables precise control of the diameter through the nozzle, allowing for reliable fabrication of light-emitting materials in a wide range of sizes.

Dr. Pyo and his team observed and experimentally measured the light emission patterns of samples fabricated with nanophotonic 3D printing technology. They also performed electromagnetic wave simulations to analyze and validate their arguments in depth. The results showed that at a diameter of 300 nanometers, internal light reflection disappears due to spatial confinement, resulting in straight-line light propagation. As a result, the emission pattern becomes highly directional.

This property can significantly improve the performance of displays, optical storage media and encryption devices. In macroscopic structures, the superposition of different light paths often leads to broad emission patterns, which can result in optical crosstalk when tightly integrated. Nanowires with highly directional emission patterns enable clear separation of signals, which eliminates distortions in visualization or interpretation.

Dr. Jaeyeon Pyo stated, “Research on optical physics at the nanoscale is challenging, especially due to the difficulty in specimen preparation, which is often high-cost and time-consuming. Our contribution demonstrates that the 3D printing method can be a versatile platform for studying optical physics owing to its simple, flexible, and low-cost characteristics.” He added, “This research will significantly contribute to the cutting-edge display technologies, and quantum physics, which are part of South Korea’s ‘National Strategic Technology Nurture Plan.”

The team expects their work to generate great interest in the fields of virtual reality, beam projectors, optical storage media, photonic integrated circuits, encryption technologies and security printing. They plan to investigate further optical phenomena at the nanoscale and use the possibilities of 3D printing to produce free-form structures.