INTEC   05402
INSTITUTO DE DESARROLLO TECNOLOGICO PARA LA INDUSTRIA QUIMICA
Unidad Ejecutora - UE
artículos
Título:
Atomic jumps during surface diffusion.
Autor/es:
J.FERRÓN; R. MIRANDA; J.J.DEMIGUEL
Revista:
PHYSICAL REVIEW B - CONDENSED MATTER AND MATERIALS PHYSICS
Editorial:
American Physical society
Referencias:
Lugar: New York; Año: 2009 vol. 79 p. 2454071 - 2454079
ISSN:
0163-1829
Resumen:
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The
characteristics of atomic displacements during surface diffusion of Cu on Cu(111) are studied by means of
Molecular Dynamics simulations. It is found that even at very low substrate
temperatures, the majority of the jumps are correlated, i.e., the displacement
directions are not randomly chosen but rather keep some sort of memory from the
previous moves and are influenced by them. Long jumps, spanning several surface
unit cells, are observed at all temperatures. From an analysis of their length
probability distribution information can be obtained about the mechanisms of
friction and energy transfer between the diffusing adatom and the substrate. Both
long jumps and recrossings (displacements in which the adatom moves back and
forth between two adjacent adsorption sites) appear with a higher activation
energy than normal diffusion. Finally, the influence of the instantaneous
atomic configuration of the substrate on the adatom´s trajectory suggests the
possibility of chaotic behavior in surface atomic diffusion.