Experimental evidence for a nonparabolic nanoscale interface shift during the dissolution of Ni into bulk Au(111)

, where x is theinterface shift and t is timed as predicted recently by computer simulation fZ. Erdelyi et al., Phys. Rev. B 69,113407 s2004dg for a binary system with restricted mutual solubility. Using x-ray photoelectron spectroscopywe investigated the shift of the interface between a thin Ni layer s3nmd deposited under UHV conditions ontop of a Aus111d single crystal during its thermally driven dissolution into the Au substrate. From the temporalevolution of the Ni-2p and Au-4f core level intensities at various fixed temperatures, a power law could beextracted for the time dependence of the interface shift s~t