Sub-micron nanostructures can now be 3D printed in freeform shapes using high-index materials that change state on command.
Fabricating complex light-steering devices usually involves a slow and flat layering process similar to making computer chips. This new technique uses two-photon light to print 3D shapes directly from a liquid precursor. The resulting structures are made of Sb2S3, a material that can be switched between different physical states. This allows for the creation of tiny, high-performance optical components that were previously impossible to build. It opens the door to 3D-printed photonic circuits that are faster and more efficient.
Two-Photon-Induced Direct 3D Printing of Freeform High-Index Phase-Change Sb2S3 Nanostructures
arXiv · 2605.01054
Chalcogenides have recently emerged as an important class of phase-change materials (PCMs) for nanophotonics, owing to their very high refractive index (RI) and low optical loss in the visible to near-infrared range. They exhibit an ultralarge RI change (> 0.7) upon phase transition, which can be triggered by multiple stimuli such as electrical bias, laser illumination or thermal heating. These properties make them highly appealing materials for flat optics and metasurface applications. Current