Multi-Layered Chiral Metamaterials Using Standard CMOS for Polarization-Dependent Mid-Infrared Imaging

Three-dimensional (3D) chiral metamaterials are structures with broken out-of-plane symmetry. Among all types of 3D metamaterials, multilayer-stacked metamaterials stand out as they have the potential for large-scale fabrication. In this work, we first demonstrate multilayered chiral metamaterials in mid-infrared regime using a standard CMOS fabrication process. Moreover, we use temporal coupled-mode theory to reveal the relationship between the twisted angle and the far-field coupling coefficient, which is validated both theoretically and experimentally. Leveraging such a platform, we further design a 5×5 array to demonstrate mid-infrared polarization-dependent imaging application.