Fig. 3: Comparison between BCDI results and FEA simulations for a triangular structure obtained with the 5-µm-side mask.

a 2D slice through the 3D reconstructed out-of-plane atom displacement along a plane parallel to the micro-triangle surface and bisecting its thickness (i.e., at z = +100 nm from the substrate upper face), the bright area is delimited by the intersection with the isosurface used in Fig. 2b; similar images (not shown) are obtained cutting with parallel planes at different heights. The displacement u_z is related to the phase Φ_z through the relation Φ_z = 4 × (2π/a_z^GaAsN) × u_z, where a_z^GaAsN is the out-of-plane lattice parameter of GaAs_1−yN_y; the color scale is in Å. b FEA simulation corresponding to the displacement map of a, obtained as described in the “Methods” section and in the Supplementary FEA section, color scale is in Å. c Displacement map obtained cutting the triangle with a plane perpendicular to the surface, and passing by one vertex and bisecting the opposite edge, the vertex is at the right of the image, the substrate-side at the bottom. d FEA simulation corresponding to the displacement map of c. The full amplitude and displacement volumes simulated by FEA are available upon request from the authors.