Multiphysics Bianisotropy in Wave--Diffusion Metamaterials

Abstract

Many physical systems, including thermoelastic solids, ionic conductors, and piezoelectric semiconductors, are governed by coupled wave-diffusion dynamics in which propagating fields coexist with dissipative transport. We develop a first-principles homogenization theory for such heterogeneous media and complement it with a scattering analysis of thermoelastic multilayers. We show that breaking spatial symmetries at finer scales induces macroscopic cross-couplings between otherwise uncoupled diffusive and propagating fields. Their signatures include strongly direction-dependent thermomechanical cross-channel scattering, offering pathways for signal manipulation in wave--diffusion metamaterials.