Catalyst nanowire interface in three dimensions. (a) 1-nm-thick slices through the nanowire over the region defined by the white bar in b. The diameter of the slices is 10 nm. (b) A 14 × 14 × 23 nm3 reconstruction of an InAs nanowire tip showing Au catalyst particle at the top. (c) One-dimensional composition profile plotted along the growth axis and through the catalyst/nanowire interface. The plotted composition is a radially averaged value within a 4-nm-diameter cylinder centered in the middle of the nanowire. From Local-Electrode Atom-Probe tomography by Danny Perea which appears in Three-Dimensional Nanoscale Composition Mapping of Semiconductor Nanowires.

Image and notes courtesy of The Seidman Group, Northwestern University Center for Atom-Probe Tomography

LEAP analysis volume (100nm x 100nm x 400nm) of an FeNiAlCr alloy (Cr – purple, Ni – green) showing three distinct phases and (b) 12nm x 10nm x 4nm sub-region showing coherency between Fe (orange) and Ni (green) atoms in a secondary FeCr precipitate.

Image courtesy of Dr. C. Stallybrass, G. Sauthoff, A. Schneider, and Y. Degas, Max-Planck-Institut für Eisenforschung, Düsseldorf.