Researchers created a silicon nanocavity that has the ability to trap light for longer than other cavities of the same dimensions.
The new design allows for a 10-fold improvement to the performance of other existing nanocavities, a University of Rochester news release reported.
The light was confined for nanoseconds, which is the amount of time it would take for the light to travel several meters under normal circumstances. The light was confined to an area that was one-hundredth the width of a human hair.
"Light holds the key to some of nature's deepest secrets, but it is very challenging to confine it in small spaces," Antonio Badolato, professor of physics at the University of Rochester and corresponding author of the Applied Physics Letters paper, said in the news release. "Light has no rest mass or charge that allow forces to act on it and trap it; it has to be done by carefully designing tiny mirrors that reflect light millions of times."
The innovation could lead to a new generation of "highly integrated nanophotonics structures," the news release reported.
Confining light is helpful because it allows it to be more easily manipulated. Trapped light can also be studied in the state where it behaves as a particle.
The team designed the device using a "genetic" (evolutionary) algorithm tool. In this approach each new nanocavity is regarded as a an individual in a population. The individuals "breed" to create a new one that is a cross between the "parents." For each new generation the algorithm chose the most fit specimens, or the ones that exhibited the longest trap times.
"Integrated nanophotonics is a new and rapidly growing field of research laying at the intersection of photonics, nanotechnology, and materials science. In the near future, nanophotonics circuits will enable disruptive technologies ranging from telecommunications to biosensing, and because they can process pulses of light extremely fast and with very low energy consumption, they hold the potential to replace conventional information-handling systems," the news release reported.
This new method produces nanocavities with the highest quality factors but also very small footprints.
