Dynamic Faceting Transitions for Dimer Type Surface Growth

Conservation laws strongly affect the scaling properties of crystal surfaces. We consider a crystal built from spherical particles, but that can deposit and evaporate only in dimer form, and do so only aligned with the one dimensional (1D) surface. Pinning valleys (hill tops) develop spontaneously and the surface facets for all growth (evaporation) biases. The scaling properties of the rough 1D equilibrium surface are anomalous. The width, $W\sim L^\alpha$, diverges with system size $L$, as $\alpha=0.25(5)$. We demonstrate that this type of faceting by pinning valleys takes place also at absorbing state type roughening transitions, where erosion at flat surface segments is forbidden.