Scanning tunneling microscopy (STM) on a sputtered and annealed Pt25Ni75(111) single crystal reveals a network of subsurface lattice mismatch dislocations caused by Platinum enrichment due to preferential sputtering and recoil mixing. Atomically resolved STM topographs are compared with simulations of these dislocations using embedded atom potentials. This allows to estimate the depth of the dislocations, and thus of the thickness of Pt enrichment, which is 3 monolayers on the 500eV Xe+ sputtered and 5 monolayers on the Ar+-sputtered surface, compatible with the depth of radiation damage.
Corresponding author: M. Schmid (schmid).
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