Interlayer Mass Transport and Quantum Confinement of Electronic States

A numerical analysis of the ripening of multilayer islands on Cu(111) shows that the Ehrlich-Schwoebel barrier for interlayer mass transport is independent of the terrace width w as long as w>wc0ex0ex=0ex0ex14±2, but vanishes for w<wc. The critical width wc corresponds exactly to the terrace width below which the surface state is pushed above the Fermi level due to quantum confinement. The Ehrlich-Schwoebel barrier is therefore correlated with the occupation of surface states.