Transforming how we control and interact with light
Light as we know it is static, rigid and typically fixed in function. But what if it didn’t have to be? That’s the question posed by the EU-funded METAmorphoses(opens in new window) project. Their bright idea: to develop dynamic, ultra-thin and flat optical devices capable of adapting, responding and reconfiguring themselves in real time. “This idea represents a major conceptual shift, one that removes long-standing constraints on how light is controlled and opens up previously inaccessible functionalities,” says Antonio Ambrosio(opens in new window), senior scientist and principal investigator at the Italian Institute of Technology(opens in new window), the project’s host institution.
Designing new metasurfaces
To turn this idea into reality, the project designed and fabricated metasurfaces from such photo-responsive materials as azopolymers, whose shape and structure can be actively rewritten using light. “Through structured illumination, we were able to encode complex optical functions onto these surfaces, erase them and reprogramme them, all without any physical contact,” explains Ambrosio. Researchers also verified, for the first time, the possibility of exfoliating molybdenum oxychloride (MoOCl₂) into a 2D material. They further probed its unprecedented optical anisotropy, highlighting its potential for extreme light confinement and enhanced sensing applications.
A new class of optical beams
The European Research Council(opens in new window) (ERC) supported project explored how their innovative metasurfaces could dynamically modulate not only the spatial structure of light, but its properties in time too. This line of research led to the creation of new classes of optical beams. “This class of so-called self-torqued beams had never been demonstrated before and offer a completely new degree of freedom in the temporal structuring of light – a freedom that may have important implications for ultrafast optics, communications and quantum manipulation,” adds Ambrosio. According to Ambrosio, METAmorphoses’ combination of material innovation, nanophotonic design and ultrafast optics allowed the project to exceed its initial expectations. “The idea of self-torqued light, for example, was not part of the original proposal,” he says. “It emerged from the fundamental questions we were asking about how light can be structured dynamically, and it ultimately became one of the defining achievements of the project.”
Pushing the boundaries of photonics
The METAmorphoses project has pushed the boundaries of what is currently possible in the field of photonics. From a scientific perspective, it provided new insights and tools that will enable others to design systems that are lighter, more compact and functionally richer than ever before. On a societal level, the project’s intelligent metasurfaces could be used to enhance medical imaging, improve optical communications, enable smart sensors and revolutionise augmented reality technologies. Furthermore, by reducing the size, weight and energy consumption of optical systems, these innovations support such EU priorities as sustainability and technological efficiency. “By expanding the photonics toolkit and showing that metasurfaces can become adaptive, dynamic and multifunctional interfaces for light, METAmorphoses will have a lasting impact on how we design compact, efficient and responsive optical systems,” concludes Ambrosio. Through two ERC Proof of Concept (PoC(opens in new window) grants), the project is now working to integrate its ideas and devices into real-world applications, including imaging, sensing and on-chip communication. One PoC has already led to a functional prototype and is currently under patent evaluation.
