Combining two light-trapping techniques for the best of both worlds
It’s not easy to control the rays of sunlight and bend them according to your wishes. It takes a lot to get a large portion of light to remain in one spot for a very long time. Light moves fast, so it is important that you are able coax the light into staying put. The benefits of being able to control a laser or moonbeam in your hand (or on a chip) are immense. Trapping and controlling the light on a microchip can lead to better lasers, sensors for self-driving vehicles that \”see\”, the creation of quantum-entangled photon pairs that can be used as secure communication and the fundamental study of the interactions between light, atoms and light.

Two technologies stand out among the many moonbeam-holding chips: the whispering gallery mode, or microrings. These are easily manufactured and trap light in various colors. Photonic crystals are more difficult to manufacture, but they are unmatched in their ability of confining light in a specific color to a small space, resulting in an extremely high intensity of light per photon.

A team of JQI researchers recently discovered a clever method to combine photonic crystals and whispering gallery modes in a single, easily manufactured device. The hybrid device they call a Microgear Photonic Crystal Ring can capture many colors of the light, while also capturing specific colors in tightly-confined, high intensity bundles. This unique combination opens up new possibilities in basic research and also for applications.

Source:
https://cmns.umd.edu/news-events/news/two-light-trapping-techniques-combine-best-both-worlds