Probing the three-dimensional strain inhomogeneity and equilibrium elastic properties of single crystal Ni nanowires

We employ three dimensional x-ray coherent diffraction imaging to map the lattice strain distribution, and to probe the elastic properties of a single crystalline Ni (001) nanowire grown vertically on an amorphous $SiO2∥Si$ substrate. The reconstructed density maps show that with increasing wire width, the equilibrium compressive stress in the core region decreases sharply while the surface tensile strain increases, and gradually trends to a nonzero constant. We use the retrieved projection of lattice distortion to predict the Young’s Modulus of the wire based on the elasticity theory.