By interference contrast microscopy and atomic-force microscopy, we observed for the first time a periodic roughening transition occurring on the surface of crystal aggregates of NH4Cl grown in agarose gel. The experiments show that the period of the roughening transitions depends on both NH4Cl concentration and agarose gel density. We suggest that this phenomenon arises from the competition of the interfacial growth and the nutrient transfer, a common but usually ignored effect in many growth systems.
ASJC Scopus subject areas
- Physics and Astronomy(all)