Tunable, On-Chip Beamsteering with Resonant, Electrically-Reconfigurable Phase Gradient Metasurfaces

The Dionne lab has developed ultrathin and compact devices for electrically driven beamsteering that fit on a semiconductor chip. These devices rely on resonant dielectric nanostructured surfaces known as "high quality factor" (high-Q) metasurfaces. By virtue of their strong light-matter interactions, our high-Q metasurfaces can be readily tuned and reconfigured, making them dynamic without mechanical manipulation. Our technology can be applied to LIDAR, LIFI, AR/VR, and optical imaging platforms where lightweight, compact and dynamic solid-state optics are desirable.

Using standard CMOS processing, we fabricate arrays of subwavelength dielectric antennas with narrow spectral features (associated with high quality factor resonances) in or nearby electrically tunable materials. The optical response of the high-Q metasurface can be modulated or reconfigured using an electric field. We have considered electro-optic materials such as Lithium Niobate. However, other effects such as localized thermal heating can also be used. The high-Q metasurfaces are only a few microns thick and can be integrated with standard optical light sources and detectors or combined in the same monolithic structure using VCSELS for extremely compact devices. Biasing can be applied across the full metasurface or across individual nanoantennas for almost complete control over the transmitted and /or reflected wavefront.

Stage of Research