amplitude of the complex shape function, which represents the physical PHYSICS AND CHEMISTRY OF HARD CONDENSED GaAsN electron density. The resolution of the reconstructed 3D imagey1-y MATTER, EARTH SCIENCES (85 nm) allows us to prove the sharpness of the manufactured profiles. SYNCHROTRON SOLEIL HIGHLIGHTS 2020 Fig. 2 also reveals that the atom displacement is rather constant in the inner triangle and the only notable variations are observed at the borders with the GaAsN:H barriers.y1-y CRISTAL & SIRIUS In Fig. 3 the out-of-plane displacement (u) maps extracted by BCDI BEAMLINES are compared to finite element analysis (FEA) simulations. Here, thez displacement volume is bisected by planes // (a) and ⊥ (c) to the triangle Associated publication surface to visualize internal sections. The simulations confirm a flat strain Imaging shape and strain in nanoscale distribution in the inner triangle and a quite sharp variation only close to engineered semiconductors for the borders. Moreover, the calculated u is in quantitative agreement with photonics by coherent x-ray diffraction. z the reconstruction, demonstrating the reliability of the imaging method. F. Berenguer, G. Pettinari, M. Felici, Fig. 3c shows the sharpness of the lateral profile of the /home/webapps/asp_fr/data/asp/publications/synchrotron-soleil/synchrotron-soleil-2020/soleil-highlights-2020-hd-ss-tc 200 nm-thick N. Balakrishnan, J. N. Clark, S. Ravy, layer, also well reproduced by FEA. A. Patané, A. Polimeni & G. Ciatto. FIGURE 3 Communications Materials, 1: art. n° 19 (2020). References [1] K. D. Jöns etal. , Nano Lett. 13, 126 (2013). [2] G. Pettinari et al. , Photonics 5, 10 (2018). [3] M. Henini, Dilute Nitride Semiconductors (Elsevier, Amsterdam, 2005). [4] G. Ciatto, Hydrogenated Dilute Nitride Semiconductors: Theory, Properties, and Applications (Pan Stanford, Singapore, 2015). [5] I . K. Robinson & R. Harder, Nat. Mater., 8, 291 (2009). Corresponding author Gianluca Ciatto Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, Microstructures with non-uniform strain distribution and sub-microscopic 91192 Gif sur Yvette, France structures were also studied (see associated publication). In the former gianluca.ciatto@synchrotron-soleil.fr case, BCDI enables a quality evaluation of the microstructures produced. In the latter case, the strain distribution remains narrow despite a larger Captions lattice mismatch with the nanostructure surroundings. FIGURE 1: Sketch of the fabrication process based on lithography-defined hydrogen masks and H-ion CONCLUSIONS AND PERSPECTIVES irradiation: after removal of the mask a triangular GaAs1yNy microstructure is left in the epilayer, We showed the high potential of BCDI for an insight into the fabrication surrounded by hydrogenated GaAs1yNy. process of novel engineered components for photonic devices. We FIGURE 2: Top: Coherent XRD pattern of a /home/webapps/asp_fr/data/asp/publications/synchrotron-soleil/synchrotron-soleil-2020/soleil-highlights-2020-hd-ss-tc 5-μm- demonstrated the capability to produce regular geometrical objects in side GaAs0991N0009 triangle, 200 nm thick. Bottom: the 500 nm – 5 µm range, with uniform strain distribution. Our results reconstruction of the phase of the complex density function, producing a 3D map of the out-of-plane atom pave the way for the realization of smaller unrelaxed nanostructures, displacement. which could be imaged exploiting the increase in the coherent photon flux foreseen with the upgrade of SOLEIL. This will enable the fine-tuning of FIGURE 3: Comparison between BCDI and FEA simulation for a /home/webapps/asp_fr/data/asp/publications/synchrotron-soleil/synchrotron-soleil-2020/soleil-highlights-2020-hd-ss-tc 5-μm-side triangle. (a) and (c): 2D the optical properties of quantum emitters via tailoring the nanostructures slices through the 3D reconstructed out-of-plane atom potential profile, hence the realization of complex nanophotonic devices. displacement along a plane // and ⊥ to the micro- triangle surface. (b) and (d) FEA simulation of the two displacement maps. 77