New technology enables the effective control of light

Prof. Hong-Gyu Park’s team publishes their paper in Nature Communications

▲ Prof. Hong-Gyu Park (Korea University), Kyoung-Ho Kim (Korea University), and Seokhyoung Kim (University of North Carolina-Chapel Hill)

Professor Hong-Gyu Park of the KU-KIST Graduate School of Converging Science and Technology and the Department of Physics conducted joint research with Professor James Cahoon of the Department of Chemistry at the University of North Carolina-Chapel Hill to develop a nano-optical switch that supports the selective guiding and optical switching of light over long distances. Implemented using silicon nanowires with a diameter of a few hundred nanometers, the nano-optical switch was tested and the results published in the renowned journal Nature Communications on July 17.

The team developed the “Encoded Nanowire Growth and Appearance through VLS and Etching” (ENGRAVE) process, a new method for fabricating nanowires with complex shapes, and succeeded in varying the diameter of the proposed nanowire. The color of the light propagating from the nanowire can be selected, and these are the first experimental results for the use of Mie resonance, the unique scattering of light in nanostructures. Because the color of light is highly sensitive to its surroundings, the optical switch can also be used as a sensor that detects changes in the environment.

The joint research serves as a new milestone in the development of optical computers that are controlled by light instead of electricity. The results open up new possibilities for the effective control of light. The nano-optical switch, a key component of optical computers, greatly reduces unnecessary heat by replacing electricity with light, and performs computations at the speed of light. In addition, the miniaturization of optical components minimizes the loss of light and facilitates the combination of optical and existing electronic components.

- Authors: Seokhyoung Kim (first author, University of North Carolina-Chapel Hill), Kyoung-Ho Kim (second author, Korea University), Hong-Gyu Park (corresponding author, Korea University), and James Cahoon (corresponding author, University of North Carolina-Chapel Hill)

- Title of Publication: Mie-coupled bound guided states in nanowire geometric superlattices, Nature Communications 9, 2781 (2018).

▲ Experimental image demonstrating the selective guiding of light along silicon nanowires of varying diameter