Subsurface ordering kinetics at
Fakultät für Physik,
Universität Konstanz - D-78457 Konstanz, Germany
2 Institute of Experimental Physics, Warsaw University - PL-00681 Warszawa, Poland
Accepted: 10 April 1999
The peculiar two-step ordering kinetics, discovered recently in time-resolved X-ray experiments on the Cu3Au(001) surface after a temperature quench to the ordered phase is analyzed within the time-dependent Ginzburg-Landau theory. Our model accounts for both the fast propagation of an ordering wave into the bulk, initiated by Au-surface segregation, and a time-delayed propagation of lateral order from the bulk to the surface. We also discuss further effects predicted by our theory, like the appearance of a characteristic penetration depth of the ordering wave and a secondary relaxation in its amplitude, which have not yet been detected experimentally.
PACS: 64.75.+g – Solubility, segregation, and mixing; phase separation / 05.70.Ln – Nonequilibrium and irreversible thermodynamics / 68.35.-p – Solid surfaces and solid-solid interfaces
© EDP Sciences, 1999