ELASTIC EFFECTS AND PHASE SEGREGATION DURING THE GROWTH OF THIN ALLOYLAYERS BY MOLECULAR-BEAM EPITAXY

We explore the effects of stress and strain on the composition modulat ions seen during the growth of thin solid films by molecular-beam epit axy when phase separation is the driving mechanism for the concentrati on inhomogeneity. A top view of the growing thin film shows lamellar a nd hexagonal patterns of phase-separated domains, the elastic effects being directly responsible for the appearance of the hexagonal order. We find that in the lamellar regime, elastically deformed lamellae are separated by undeformed interfaces, while in the droplet phase, the s oft component is deformed and wraps the hard component. We also discus s the effects of crystal anisotropy in our system.