Israeli-linked breakthrough pushes light control to record speeds
Researchers have reached a new milestone in photonics by controlling light beams at speeds previously thought impossible. A team involving experts from Tel Aviv University and Caltech developed a metasurface capable of steering and shaping light in just 74 femtoseconds. This duration is less than one-tenth of a trillionth of a second, a timeframe where light travels a distance shorter than the width of a human hair.
The core of this breakthrough is an ultrathin layer of silicon populated by microscopic structures. These structures are smaller than the wavelength of light itself. When a short laser pulse hits this surface, the material properties of the silicon change momentarily. This allows the system to direct or reshape light beams without the need for mechanical parts like mirrors or lenses. In experimental tests, the team successfully steered beams by up to 13 degrees while simultaneously generating complex light patterns.
Dr. Lior Michaeli, now heading the Meta-Optomechanics Lab at Tel Aviv University, noted that the main challenge was amplifying a typically weak effect. By precisely engineering the metasurface, the team ensured the effect was strong enough to measure and apply. This innovation allows the same component to perform different tasks based on the specific illumination pattern used, providing a level of flexibility that mechanical systems cannot match.
While this work currently sits in the phase of basic research, the implications for future technology are clear. Modern computing and communications systems rely on converting light signals into electrical signals and back again. By controlling light directly at these speeds, researchers move closer to building optical computers that process information using light itself. This capability is expected to impact fields ranging from high-speed communications and advanced sensors to quantum photonics.
Future developments will aim for even faster operation as researchers look to shorten laser pulses further. The study, published in Nature Nanotechnology, serves as a foundation for engineers to manipulate light-matter interactions in ways that were once purely theoretical. Dr. Michaeli and his colleagues continue to refine these engineered structures to create tools for precise light control and information processing.