Figure 1.

Schematic of experimental-driven methodology (a) Conceptual overview of methodology, including the nonlinear conversion of optical patterns to THz structural waves and the retrieval of transmission properties of the scattering medium defined in terms of a coherent transfer matrix. The full knowledge of the coherent transfer matrix retrieved using an orthogonal set of patterns can be used to achieve scattering-assisted focusing at the output of the scattering medium. (b) Input THz pulse electric-field profile. (c) Scattered THz pulse collected at a generic mth output pixel. (d) Intensity spectral density of the input THz field. (e) Intensity spectral density of the scattered THz pulse as collected at a generic mth pixel. In our simulations, we considered a 1 nJ THz pulse of duration 250 fs at the input with 40 dB SNR per pixel. The 6.4 × 6.4 mm² sample illumination area is spatially sampled at 200 μm resolution, corresponding to a number of pixels of 32 × 32.