Two Dimensional Equilibrium Surface Roughness for Dissociative Dimer Dynamics

Equilibrium crystal surfaces, constrained to equilibrate by means of dissociative dimer deposition and evaporation, have anomalous global surface roughness. We generalize earlier results for one dimensional interfaces to two dimensions. The global surface width scales with surface size L as W^2 \sim log [L/ (log L)^{1/4}] instead of the conventional form W^2 \sim log L. The surface roughening transition does not change in nature, but its location is subject to a large and slowly varying logarithmic finite-size-scaling shift.