Kinetics of fast island decay on Ag(111)

The kinetics of fast island decay on Ag(111) close to steps has been studied in scanning tunneling microscopy experiments and atomistic total energy calculations. We show that a breakdown of the step-edge barrier is not sufficient to explain the decay rates observed during fast decay events. From the interplay between experiments and theory, we instead propose that fast decay originates from concerted diffusion processes, which bypass the detachment barrier of atoms from kinks and step sites.