Slowing down light on microchips is a step toward a high-technology future. Chinese scientists at the Shenzhen Institute of Advanced Technology, part of the Chinese Academy of Sciences, have discovered a way to slow down light on microchips by more than 10,000 times. The research, published Jan. 5 in the journal Nano Letters, could significantly improve the performance of photonic chips used in light sensing, communications, and computing. Photonic chips process photons rather than electrons like traditional chips. They are similar to electronic chips in terms of calculation accuracy, but have the advantage of lower power consumption and faster operation speed.
Dr. Li Guangyuan, a senior researcher at the Shenzhen Institute, points out that slowing down the speed of light increases its energy density, improving the interaction between light and devices and increasing efficiency. Lee’s team has developed a photonic chip that slows light by about 20% and more than 10,000 times compared to traditional methods, while minimizing energy loss. The main way to control the speed of light has so far relied on metasurfaces made of nanostructures that change the amplitude and phase of light. However, light is lost due to the absorption and scattering of light by these artificial atoms.
To solve this problem, Lee’s team improved the materials used and the structural design. In particular, they used transparent materials such as silicon nitride and titanium dioxide, which do not absorb light in the visible spectrum. Furthermore, the researchers improved the concept of surface lattice resonance by incorporating periodic surface patterns of silicon nanodisks to reduce energy loss.
This technology could also reduce the cost of manufacturing photonic chips and expand their applications. Using metasurface technology, photonic chips can be made as thin as stickers or building blocks and can be functionally folded, Li said, which allows for short interaction lengths to It is said that the performance of devices such as sensors, lasers, and LEDs that are subject to limitations will be improved. Conventional thin photonic chip.