  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 Si02 || 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.
