3D Nanoprinting of Multifunctional MgO Transparent Ceramics

Transparent ceramics face fabrication challenges in achieving high-resolution 3D architectures with optical isotropy and thermal/mechanical stability. While two-photon lithography (TPL) enables nanoscale 3D printing, existing inorganic TPL materials suffer from opacity, big shrinkage, and costly postprocessing. Here, we report a solvent-free, high-loading Mg-cross-linked photoresist for TPL fabrication of sub-200 nm 3D MgO transparent ceramics with high fidelity via two-step sintering. With a high-purity cubic lattice, defect-free and fully dense MgO structures exhibit a wide range of transparent thicknesses. Demonstrations include excellent optical imaging, focusing capabilities, and stable mechanical and optical durability of MgO under various harsh working conditions, like high temperature and high-energy laser radiation. This simple and relatively low-cost method also showcases a fiber-integrated micro-optic device for high-intensity laser systems. This synergy of nanoscale precision, wide-thickness transparency, and outstanding stability will position 3D MgO transparent ceramics as next-generation optical components to make micro-optical devices with high damage thresholds.