Regions of varying chemical ordering determined in an FePt nanoparticle. By mapping individual atomic coordinates with 20 pm precision, electron tomography can determine chemical ordering in an FePt particle. While some types of chemical ordering (L10) have magnetic anisotropy, which is desirable for magnetic memory applications, others (L12, A1) do not. This reconstructed data maps the chemical ordering with unprecedented detail.
Image credit Colin Ophus.