Metasurface-enabled additive manufacturing via two photon polymerization

Laser-based 3-D nanoprinting exemplified by two photon polymerization (TPP) has emerged as a practical route for additive manufacturing of sub-wavelength scale structures with broad applications in photonic packaging, nanofluidics, nanoelectromechanical systems, drug delivery, tissue engineering, and beyond. Conventional TPP relies on compound refractive lenses for light focusing. Here we present a novel alternative approach leveraging optical metalenses as the light manipulation element for versatile TPP fabrication. Using an inverse design algorithm, we show that the point spread function (PSF) of the metalens can be custom tailored to realize a variety of TPP writing modes, enabling fabrication of unconventional geometries difficult to process with traditional TPP. We demonstrated integration of metalenses with both commercial and home-built TPP systems, and experimentally implemented TPP to writing of 3-D polymer microstructures.