THz Multi-Layer Imaging via Nonlinear Inverse Scattering


In this paper, to mitigate the nonlinear shadow effects in Terahertz time-domain spectroscopy (THz-TDS) multilayer imaging, we utilize a one-dimensional (1D) nonlinear model to capture the interaction between the dielectric permittivity profile and the THz wavefield and recover the multi-layer structure by solving a 1D nonlinear inverse scattering via an iterative and sequential optimization over frequency. Numerical results confirm the effectiveness of the proposed method.