Topological Optimization Framework for the Automated Design of 3D Printable THz Lens Antennas

Electromagnetic topological optimization holds the promise of the fully automated design of electromagnetic structures such as antennas, waveguides, metasurfaces and metamaterials; however, it can often yield designs that are incompatible with fabrication processes. In this work, we describe a multiphysics topological optimization framework that combines structural finite element analysis and electromagnetic finitedifference time-domain simulation to realize fabricable structures which meet specified electromagnetic design objectives. As a demonstration, the framework is applied towards the design of G-band low-profile leaky lens antennas suitable for future 6G communication applications. The 5λ0 radius, 2λ0 thick leaky lens antenna is compatible with stereolithography 3D printing and displays a realized gain of 23 dBi at 0.2 THz with a low sidelobe level of -20 dB. We foresee the proposed framework being applicable to a wide range of electromagnetic design problems intended for fabrication using additive manufacturing techniques.