Cr impurities in the Fe(001) surface
STM image, 35 nm x 35 nm, of single substitutional Cr impurities (small bumps) in the Fe(001) surface.

Reference: Atomic-scale Observations of Alloying at the Cr-Fe(001) Interface, A. Davies, J.A. Stroscio, D.T. Pierce, and R.J. Celotta, Phys. Rev. Lett. 76, 4175 (1996). Electron Physics Group

Scanning Tunneling Microscope Exhibit