A new study has demonstrated time reflections with light waves, which could lead to new ways to control light, such as photonic time crystals. Time reflections occur when the medium in which a wave is traveling suddenly changes its optical properties. Researchers have created the first time interface for light, using a metamaterial. When a light wave enters the time interface, the signal gets reversed, as if it were getting played backwards. The researchers also showed that multiple time interfaces can be combined to interfere with each other. Time interfaces may find use in wireless communications, radar technologies, and optical computing, and can enable time reversal quickly and with little energy. Additionally, time interfaces may help scientists develop exotic ways to control light, such as photonic time crystals, which selectively amplify incoming signals and control their propagation.
| Signal | Change | 10y horizon | Driving force |
|---|---|---|---|
| Time reflections with light waves | Control light in new ways | Advancements in wireless communications and radar | Potential applications in wireless communications, radar technologies, and photonic computing |
| New time interface for light created | Change optical properties to generate time reflections | Faster, stronger, and uniform time reflections | Ability to change a material’s optical properties in a fast and uniform way |
| Time interfaces can stretch or compress | Abruptly change the color of light signals | Exotic ways to control light | Development of photonic time crystals and ability to control light properties |
| Time interfaces enable quick time reversal | Reverse signals quickly and with little energy | Exotic ways to control light | Ability to rapidly reverse the order of signals with little energy |
| Potential use in wireless communications | Improve signal processing | Advancements in wireless communications and radar | Need for efficient signal processing in wireless communications and radar |
| Potential use in photonic time crystals | Control light propagation in unusual ways | Advancements in photonic time crystals | Desire to selectively amplify incoming signals and control their propagation |