Large-Area 3D-Printed Chiral Metasurface Composed of Metal Helices

摘要

An original design for chiral metasurfaces formation is proposed. The hybridrnfabrication approach is based on the 3D printing of polymer substrates withrna shape-generating “helical” relief, molding, and subsequent shadow metalrndeposition. The formed double-layer grating of multiturn metal helices rotatesrnthe polarization plane of sub-terahertz and microwave radiation through anrnangle in excess of 40°. Both experimentally and in numerical simulations,rnit is demonstrated that re-reflection phenomena occur in the “metal helix–rnpolymer substrate” hybrid structure. Those phenomena permit controlrnof polarization-plane rotation, ellipticity, and asymmetric transmission.rnMultiplication of printed structures with 3D helices achieved by using thernmolding technique enables the formation of large-area chiral metasurfaces.rnThe advantages of the proposed metasurface include easy fabrication of thernsystem, the possibility of its scalability to other frequency ranges, and thernpossibility of using systems based on such metasurfaces in highly efficientrnpolarization transformers.