{ "id": "1711.09652", "version": "v1", "published": "2017-11-27T12:36:51.000Z", "updated": "2017-11-27T12:36:51.000Z", "title": "Growing interfaces: A brief review on the tilt method", "authors": [ "M. F. Torres", "R. C. Buceta" ], "comment": "11 pages, 4 figures", "categories": [ "cond-mat.stat-mech" ], "abstract": "The tilt method applied to models of growing interfaces is a useful tool to characterize the nonlinearities of their associated equation. Growing interfaces with average slope $m$, in models and equations belonging to Kardar-Parisi-Zhang (KPZ) universality class, have average saturation velocity $\\mathcal{V}_\\mathrm{sat}=\\Upsilon+\\frac{1}{2}\\Lambda\\,m^2$ when $|m|\\ll 1$. This property is sufficient to ensure that there is a nonlinearity type square height-gradient. Usually, the constant $\\Lambda$ is considered equal to the nonlinear coefficient $\\lambda$ of the KPZ equation. In this paper, we show that the mean square height-gradient $\\langle |\\nabla h|^2\\rangle=a+b \\,m^2$, where $b=1$ for the continuous KPZ equation and $b\\neq 1$ otherwise, e.g. ballistic deposition (BD) and restricted-solid-on-solid (RSOS) models. In order to find the nonlinear coefficient $\\lambda$ associated to each system, we establish the relationship $\\Lambda=b\\,\\lambda$ and we test it through the discrete integration of the KPZ equation. We conclude that height-gradient fluctuations as function of $m^2$ are constant for continuous KPZ equation and increasing or decreasing in other systems, such as BD or RSOS models, respectively.", "revisions": [ { "version": "v1", "updated": "2017-11-27T12:36:51.000Z" } ], "analyses": { "keywords": [ "growing interfaces", "tilt method", "brief review", "continuous kpz equation", "nonlinear coefficient" ], "note": { "typesetting": "TeX", "pages": 11, "language": "en", "license": "arXiv", "status": "editable" } } }