  We present a detailed characterization of the growth dynamics of
Ga(Al)As(111)A surfaces. We develop a theoretical growth model that well
describes the observed behavior on the growth parameters and underlines the
Ehrlich-Schwoebel barrier as leading factor that determines the growth
dynamics. On such basis we analyze the factors that lead to the huge observed
roughness on such surface orientations and we identify the growth conditions
that drive the typical three-dimensional growth of Ga(Al)As(111)A towards
atomically flat surface. GaAs/AlGaAs quantum wells realized on optimized
surface (<0.2 nm roughness) show a record low emission linewidth of 4.5 meV.

Materials Science