Growth behavior of interfaces is usually described by a power-law of the growth in time of the interface width. This general scaling picture is an average behavior description, which may not be valid when only a finite number of interfaces is considered. In this work we study theoretically and experimentally the growth behavior of single interfaces and show that the growth of the interface width always exhibits a non-monotonic, fluctuating behavior. We study numerically the Quenched-noise Kardar-Parisi-Zhang (QKPZ) equation, using different noise distributions, and show that this behavior results from competing mechanisms of normal growth and surface tension forces in this equation. We define a new measure of the interface width fluctuations and present a way to extract the correlation length of the interface from these fluctuations.
Bibliographical noteFunding Information:
This research was supported by The αsrael Science Foundation (grant No. 1342/04).
- Correlation length
- Interface dynamics
- QKPZ equation