INTERFACE GROWTH DYNAMICS: RELATION BETWEEN FRACTAL GEOMETRY OF
THE SURFACE AND THE EXPONENTS OF KARDAR-PARISI-ZHANG EQUATION
Aluno: Washington Soares Alves
Keywords: Kardar-Parisi-Zhang Equation, Growth Exponents, Fractal Dimension, Single-Step
Model.
Growth phenomena are observed in various situations, such as in growth of thin films, bacteria
colony, tumors, among others. Therefore, the study of such phenomena is of utmost importance
from both theoretical and experimental point of view. In this work, we present the basic concepts
used in study of growth phenomena, followed by the growth equations as the Edwards-Wilkinson
equation (EW) and the Kardar-Parisi-Zhang equation (KPZ), together with their exponents,
determine their respective classes of universatility. We also present the definition of cellular
automata and its application in random deposition growth models, ballistic deposition, etching and
Single-Step (SS). In the recent work of Gomes-Filho and collaborators [Result in Physics, 104.435
(2021)], the authors associated the fractal dimension of the interface with the growth exponents for
KPZ, presenting explicit values for them. In this work we investigate the fluctuation-dissipation
theorem for the KPZ equation through computer simulations of the SS model. Our results showed
that the intensity of the applied noise is altered in the manner that the roughness of the interface
evolves in time, tending to a constant value in the stationary regime (effective noise), being it
associated with the fractal dimension of the interface. Thus, our results corroborate the theory
proposed by Gomes-Filho and collaborators.