Researchers have already shown that light can be slowed down in some situations, and a recent study shows how to accomplish it in a way that looks to be among the most practical yet.
The Chinese Academy of Sciences and Guangxi University academics who made the breakthrough claim that optical communication and computing could both benefit from their approach.
The speed at which light travels through empty space is 299,792 kilometers (or around 186,000 miles) per second. However, this remarkable velocity begins to slow down if you introduce a jumble of electromagnetic fields in its path, like those surrounding regular stuff.
The majority of transparent materials will only slightly delay light. Light bends when it moves from one medium to another due to variations in speed. However, in order to really apply the brakes, unique materials such as photonic crystals or even ultra-cooled quantum gasses are needed.
The researchers state in their published report, “We envision that our work provides an entirely new direction for realizing ultra-strong light-matter interactions in nanophotonic chips.”
The new technique expands upon electromagnetically induced transparency (EIT), which converts opaque gas into transparent by manipulating electrons inside the gas as it is held in a vacuum by a cunning use of laser trickery.
This means that although laser light can travel through, its speed is reduced due to manipulation. For physicists, this makes it extremely intriguing, but the method also implies that a significant amount of light and energy are lost in the process.
The researchers created a novel material that slows down light using some of the EIT’s light-controlling principles in order to lessen this loss and increase the efficiency of the entire system. The substance is an artificial, two-dimensional structure having characteristics not seen in any natural surface, or metasurface.
The team’s metasurfaces, which resemble modern computer chips due to their incredibly thin silicon layers, outperformed earlier alternatives in terms of energy storage and release (light, in this case).
The researchers’ findings indicate that under this arrangement, light can be slowed down by more than 10,000 times. When compared to other similar approaches, the light loss is simultaneously decreased by a factor of more than five.
The location of the smallest components of the metasurface, referred to as meta-atoms, is crucial to the new strategy. In this instance, they are practically merging, which has an impact on how light is managed as it moves through.
Better control over the speed at which light travels is the ultimate goal of all this intricate research. There are a ton of possible uses for light because it is essential to everything from broadband internet to quantum computers.
Though it’s not the only method beyond the natural dimming of light that occurs in materials like water that scientists have discovered, its efficacy and scalability make it a potential avenue for additional research.
“With these findings, our study opens a new route for tailoring light flow in metasurfaces,” the authors write.
