Researchers create Real-Time control of crystal layer twist and spacing

Researchers from Harvard SEAS, Stanford University, and UC Berkeley have developed an on-chip sensor using twisted moiré photonic crystals with MEMS technology, enabling real-time control of crystal layer twist and spacing. The device can simultaneously detect detailed polarization and wavelength information, published in Nature Photonics, funded by NSF, DARPA, U.S. Air Force Office of Scientific Research, and the U.S. Office of Naval Research. Fabrication was done at Harvard’s Center for Nanoscale Systems. Applications include quantum computing, data communications, satellites, and medical imaging.

Twisted moiré photonic crystals are an advanced type of optical metamaterial that leverage the interaction between two layered structures when they are slightly shifted or twisted relative to each other. This creates intricate patterns, akin to moiré effects observed in overlaid fabrics, which enable precise control over light properties such as phase, polarization, and wavelength. Adjusting the twist angle and spacing between layers allows these materials to be fine-tuned to manipulate light simultaneously, potentially replacing multiple optical components with a single device.

A significant challenge in utilizing twisted moiré photonic crystals was integrating them into devices capable of real-time control over their structural parameters. Researchers from Harvard, Stanford, and UC Berkeley addressed this by developing an on-chip sensor using MEMS technology. This innovation allows dynamic adjustment of the gap and angle between crystal layers, enabling active tuning of optical properties.

The resulting device demonstrates hyperspectral and hyperpolarimetric imaging capabilities, capturing detailed electromagnetic spectrum and polarization information at each pixel. These abilities are particularly valuable for applications requiring precise light analysis, such as quantum computing, data communications, satellite technology, and medical imaging. The ability to dynamically adjust structural parameters enhances the device’s utility across these domains.

Fabrication and scalability of twisted moiré photonic crystal devices

The integration of twisted moiré photonic crystals into real-time devices has been advanced through the use of MEMS technology, enabling dynamic control over structural parameters such as layer spacing and twist angle. This capability allows for active tuning of optical properties, including phase, polarization, and wavelength, which are critical for manipulating light in applications ranging from imaging to communication systems.

The development of this sensor represents a significant step forward in leveraging twisted moiré photonic crystals for practical use. By enabling real-time control over structural elements, researchers have expanded the potential for integrating these materials into advanced optical systems, paving the way for future innovations in optical technology.