The device developed at CUNY is the first to combine two key advantages for nonlinear light generation, a process where light of one color is transformed into another. It operates using a special collective resonance known as a quasi–bound state in the continuum, which traps and amplifies incoming infrared light across the entire surface. At the same time, each tiny component on the metasurface is rotated in a carefully designed pattern, allowing the emitted light to gain a position-dependent phase, similar to the effect produced by an integrated lens or prism.

Figure 1. Ultra-Thin Device Creates a Microscopic Spotlight Effect.

Generating and Steering Third-Harmonic Light

Due to this unique structure, the chip generates third-harmonic light, meaning the emitted light has a frequency three times higher than the incoming beam. The design also allows the beam to be directed toward specific directions. When the polarization of the incoming light is switched, the direction of the outgoing beam also changes, offering a simple way to control beam steering. Figure 1 shows Ultra-Thin Device Creates a Microscopic Spotlight Effect

Toward Compact Light Sources and On-Chip Photonics

The capability to efficiently generate and control new colors of light using a flat chip could support many future technological applications.

“This platform provides a pathway toward ultra-compact light sources and beam-steering components for technologies such as LiDAR, quantum light generation, and optical signal processing, all integrated directly onto a chip,” said lead author Michele Cotrufo, a former postdoctoral fellow at CUNY and currently an assistant professor at the University of Rochester. “Since the concept relies on geometric design rather than a single specific material, it can be extended to a variety of nonlinear materials and different wavelengths of light, including the ultraviolet.”

Researchers suggest that future versions of the technology may stack or combine multiple metasurfaces, each tuned slightly differently. This strategy could enable the system to function efficiently across a wider range of wavelengths.

What the Ultra-Thin Device Does

Scientists have developed an ultra-thin optical device that can control light in a very precise way, similar to how a tiny spotlight focuses a beam onto a specific spot. Instead of using bulky lenses or mirrors, the device uses a flat metasurface made of extremely small structures. These microscopic elements interact with incoming light and shape how it moves, allowing the device to concentrate or direct the light with high accuracy.

How the Technology Works

The metasurface is designed with carefully arranged nano-structures that manipulate the phase and direction of light waves. When infrared light hits the surface, a special resonance effect strengthens the interaction between light and the material. At the same time, the tiny elements on the surface are rotated in a specific pattern, which changes how the outgoing light spreads. This design lets the device both generate new light frequencies and steer the beam, almost like having a built-in lens or prism on a microscopic scale.

Why It Matters for Future Technology

Because the device is extremely thin and can be integrated onto a chip, it could help create compact optical systems for future technologies. Potential applications include LiDAR sensors used in autonomous vehicles, quantum light sources for advanced computing, and faster optical communication systems. By combining efficiency with precise beam control, this technology could make next-generation photonic devices smaller, more powerful, and easier to integrate into electronic chips.

Source: SciTECHDaily

Cite this article:

Priyadharshini S (2026), Microscopic Spotlight Effect Achieved with Ultra-Thin Device, AnaTechMaz, pp. 452