Morphological symmetry breaking during epitaxial growth at grazing incidence

It is shown that, in submonolayer growth at off-normal incidence, even much less than 1% of transfer from the condensation energy of the deposited ato ms into adatom motion is sufficient to induce a net adatom current from the illuminated edge of a two-dimensional island to the other edges, thereby b reaking the island symmetry. Such a symmetry breaking phenomenon is most pr onounced for deposition at grazing incidence. Comparison between our theore tical predictions and existing experimental results confirms the general va lidity of the model.