We review our recent progress on 3D and 4D laser printing on the micrometer and nanometer scale. This includes light-responsive metamaterial architectures based on liquid-crystal elastomers, the local director of which we align in situ by means of quasi-static electric fields during the 3D multi-photon printing process. Furthermore, we introduce in-situ diagnostics by means of optical-coherence tomography (joint work with ZEISS).
Finally, we report on our efforts on using two-step absorption instead of two-photon absorption. Focus-scanning 3D printing based on one-color two-step absorption allows for democratizing 3D nanoprinting (joint work with Nanoscribe). Projection-based light-sheet 3D printing using two-color two-step absorption supports printing rates approaching 107 voxels/s at voxel volumes below 1 µm3.