Ultrafast Laser Assembly of Metasurfaces with Large Scale Fabrication Capabilities

Modern nanophotonic devices are redefining what can be achieved in terms of manipulating light, as they provide a versatile design platform for moulding the propagation of light at will. In particular, free-space and integrated optical metasurfaces (MS) are currently offering a promising route towards the realisation of compact and lightweight optical components for sophisticated engineering of the amplitude, phase and polarisation of electromagnetic waves, which could ultimately replace current conventional bulky optics in a near future. Yet, today the realisation of MS is based on the combination of precise, but time-consuming and energy inefficient nanofabrication techniques that rely on expensive and highly specialised equipment operated in strict cleanroom environments: conditions which are beyond the capability of a vast majority of industrial entities.The main objective of METASCALE is to develop alternative fabrication techniques based on ultrafast laser processing (ULP) strategies, towards the realisation of MS operating in the visible and infrared spectrum. Such processes will be compatible with large-scale, cost-effective and green manufacturing routines, thus appropriate for current industrial environments. For this purpose, METASCALE will specifically focus on the physical fabrication and testing of pre-designed metasurfaces, based on ultrafast laser assembly techniques such as direct laser writing, or laser interference patterning. Such ULP techniques are highly versatile and repeatable in terms of surface micro- and nano-patterning, but at the same time require a deep understanding and careful adjustment of a broad range of linear and non-linear laser-matter interaction mechanisms and their related timescales. METASCALE is therefore an interdisciplinary and collaborative effort involving many scientific branches ranging from material science to ultrafast optics or computational physics.