Circuit-based Modeling and Inverse Design of Metastructures

Passcode: 20210903

Metamaterials are subwavelength textured structures with effective medium responses. Metastructures are similar but they do not require a material equivalence. Their ability to tailor electromagnetic responses has provided engineers with unprecedented control over the amplitude, phase, and polarization of electromagnetic wavefronts. This extreme control has allowed them to find a wide range of applications including wireless communication, imaging, wireless power transfer, and cloaking. However, as new applications emerge and greater control over wavefronts is desired, the development of methods for modeling and designing metastructures has emerged as an important problem.

Earlier work has shown that circuit-based modeling methods are powerful tools for analyzing and designing metamaterial devices. However, these models were limited to two-dimensional materials with anisotropic permittivities and permeabilities. In the first part of this dissertation work, these models are generalized to include two-dimensional omega bianisotropic responses. The second part of the work introduces a computational inverse design procedure for multi-input multi-output (MIMO) metastructures that uses a circuit-based solver to model metastructured devices. The circuit-based solver significantly reduces the computational cost of the forward problem. Combined with the adjoint variable method, it allows for the design of electrically-large MIMO metastructures. The design procedure’s ability to realize practical devices is verified experimentally through the realization of metastructured beamformers.

Chair: Professor Anthony Grbic