research
A photonic diode using a nitride semiconductor rod can increase the possibility of developing all-optical integrated circuits, an alternative to conventional integrated circuits.
Professor Yong-Hoon Cho's research team from the Department of Physics, KAIST, developed a photonic diode which can selectively transfer light in one way, using semiconductor rods.
The photonic diode has a diameter of hundreds of nanometers (nm) and a length of few micrometers. This size enables its use in large-scale integration (LSI). The diode’s less sensitivity towards polarized light angle makes it more useful.
In an integrated circuit, a diode controls the flow of electrons. If this diode controls light rather than electrons, data can be transferred at high speed, and its loss is minimized to a greater extent. Since these implementations conserve more energy, this is a very promising future technology.
However, conventional electronic diodes, made up of asymmetric meta-materials or photonic crystalline structures, are large, which makes them difficult to be used in LSI. These diodes could only be implemented under limited conditions due to its sensitivity towards polarized light angle.
The research team used nitride semiconductor rods to develop a highly efficient photonic diode with distinct light intensities from opposite ends.
The semiconductor rod yields different amount of energy horizontally. According to the research team, this is because the width of the quantum well and its indium quantity is continuously controlled.
Professor Cho said, "A large energy difference in a horizontal direction causes asymmetrical light propagation, enabling it to be operated as a photonic diode." He added that “If light, instead of electrons, were adopted in integrated circuits, the transfer speed would be expected as great as that of light.”
The research findings were published in the September 10th issue of Nano Letters as the cover paper.
Under the guidance of Professor Cho, two Ph.D. candidates, Suk-Min Ko and Su-Hyun Gong, conducted this research. This research project was sponsored by the National Research Foundation of Korea and KAIST’s EEWS (energy, environment, water, and sustainability) Research Center.
Figure Description: Computer simulated image of photonic diode made of semiconductor rod implemented in an all-optical integrated circuit
-
research KAIST, Production Temperature ↓ by 500°C, Power Output ↑ 2x… Next-Generation Ceramic Electrochemical Cell Reborn
<(Top row, from left) Professor Kang Taek Lee, Ph.D candidate Yejin Kang, Dr. Dongyeon Kim, (Bottom row, from left) M.S candidate Mincheol Lee, Ph.D candidate Seeun Oh, Ph.D candidate Seungsoo Jang, Ph.D candidate Hyeonggeun Kim> As power demand surges in the AI era, the “protonic ceramic electrochemical cell (PCEC),” which can simultaneously produce electricity and hydrogen, is gaining attention as a next-generation energy technology. However, this cell has faced the techni
2025-12-05 -
event Robot-Operated Space Station Construction Goal... 'In-space Servicing and Manufacturing Research Center' Launched
<Plaque Handover Ceremony. (From left) Jae-Hung Han, Director of the Space Research Institute, Ju-won Kang, Head of Engineering Group at the National Research Foundation of Korea Basic Research Headquarters> KAIST's Space Research Institute announced on the 24th of October that it officially launched the 'Innovative Research Center for the Development of Core Technologies in In-space Servicing and Manufacturing (ISMRC)' at the KAIST Academic Cultural Center on Friday, October 24. About
2025-10-24 -
research Batteries Make 12Minute Charge for 800km Drive a Reality
<Photo 1. (From left in the front row) Dr. Hyeokjin Kwon from Chemical and Biomolecular Engineering, Professor Hee Tak Kim, and Professor Seong Su Kim from Mechanical Engineering> Korean researchers have ushered in a new era for electric vehicle (EV) battery technology by solving the long-standing dendrite problem in lithium-metal batteries. While conventional lithium-ion batteries are limited to a maximum range of 600 km, the new battery can achieve a range of 800 km on a single charge
2025-09-04 -
research Is 24-hour health monitoring possible with ambient light energy?
<(From left) Ph.D candidate Youngmin Sim, Ph.D candidate Do Yun Park, Dr. Chanho Park, Professor Kyeongha Kwon> Miniaturization and weight reduction of medical wearable devices for continuous health monitoring such as heart rate, blood oxygen saturation, and sweat component analysis remain major challenges. In particular, optical sensors consume a significant amount of power for LED operation and wireless transmission, requiring heavy and bulky batteries. To overcome these limitations
2025-07-30 -
research KAIST Presents a Breakthrough in Overcoming Drug Resistance in Cancer – Hope for Treating Intractable Diseases like Diabetes
<(From the left) Prof. Hyun Uk Kim, Ph.D candiate Hae Deok Jung, Ph.D candidate Jina Lim, Prof.Yoosik Kim from the Department of Chemical and Biomolecular Engineering> One of the biggest obstacles in cancer treatment is drug resistance in cancer cells. Conventional efforts have focused on identifying new drug targets to eliminate these resistant cells, but such approaches can often lead to even stronger resistance. Now, researchers at KAIST have developed a computational framework to pr
2025-07-08