Anomalous scaling in a nonlocal growth model in the Kardar-Parisi-Zhang universality class

4 pages, 3 figures.-- PACS nrs.: 05.40.+j, 05.70.Ln, 68.35.Fx, 81.15.Pq.-- ArXiv pre-print available at: http://arxiv.org/abs/cond-mat/9802033Final publisher version available Open Access at: http://gisc.uc3m.es/~cuerno/publ_list.htmlWe study the interface dynamics of a discrete model previously shown [A. Sánchez, M. J. Bernal, and J. M. Riveiro, Phys. Rev. E 50, R2427 (1994)] to quantitatively describe electrochemical deposition experiments. The model allows for a finite density of biased random walkers which irreversibly stick onto a substrate. There is no surface diffusion. Extensive numerical simulations indicate that the interface dynamics is unstable at early times, but asymptotically displays the scaling of the Kardar-Parisi-Zhang universality class. During the time interval in which the surface is unstable, its power spectrum is anomalous; hence, the behaviors at length scales smaller than or comparable with the system size are described by different roughness exponents. These results are expected to apply to a wide range of electrochemical deposition experiments.Work at GISC has been supported by CICyT (Spain) Grant No. MAT95-0325 and DGES (Spain) Grant No. PB96-0119.Publicad