Related papers: Spontaneous spiral patterns etched on Germanium
We study the behaviour of interacting self-propelled particles, whose self-propulsion speed decreases with their local density. By combining direct simulations of the microscopic model with an analysis of the hydrodynamic equations obtained…
Spontaneous formation of geometric patterns is a fascinating, ubiquitous process that provides fundamental insights into the roles of symmetry breaking, anisotropy and nonlinear interactions in emergent phenomena. Here we report dynamic,…
We demonstrate high-quality epitaxial germanium (Ge) films on a metallic silicide, Fe3Si, grown directly on a Ge(111) substrate. Using molecular beam epitaxy techniques, we can obtain an artificially controlled arrangement of silicon (Si)…
It is proposed that the spatial (and temporal) patterns spontaneously appearing in dissipative systems maximize the energy flow through the pattern forming interface. In other words - the patterns maximize the entropy growth rate in an…
We report experiments, modeling and numerical simulations of the self--assembly of particle patterns obtained from a nanometric metallic square grid. Initially, nickel filaments of rectangular cross section are patterned on a SiO$_2$ flat…
Given a distribution of defects on a structured surface, such as those represented by 2-dimensional crystalline materials, liquid crystalline surfaces, and thin sandwiched shells, what is the resulting stress field and the deformed shape?…
Chemical gardens are mineral aggregates that grow in three dimensions with plant-like forms and share properties with self-assembled structures like nano-scale tubes, brinicles or chimneys at hydrothermal vents. The analysis of their shapes…
It is known that ion-irradiation can lead surfaces to spontaneously develop patterns with characteristic length scales on the order of only a few nanometers. Pattern formation typically occurs only for irradiation angles beyond a critical…
The contact of a hydrogel during the rotational shearing on glass surface in concentrated polymer solution was observed in situ. Dynamic contact patterns that rotate in-phase with the rotational shearing of the gel were observed for the…
The present paper is dedicated to the structural study of crystallographic peculiarities appearing in epitaxial films of metastable epsilon iron oxide ($\varepsilon$-Fe$_2$O$_3$) grown by pulsed laser deposition onto a semiconductor GaN…
Freckles, one of the common defects in blades used in heavy duty gas turbines, hugely deteriorates blades mechanical properties and liability under service conditions. Thermal-solutal convection theory is a widely adopted formation…
Since the 1950s Heisenberg and others have attempted to explain the appearance of countable particles in quantum field theory in terms of stable localized field configurations. As an exception Skyrme's model succeeded to describe nuclear…
When ultrathin metal films are subjected to multiple cycles of rapid melting and resolidification by a ns pulsed laser, spatially correlated interfacial nanostructures can result from a competition among several possible thin film…
Worm-like filaments that are propelled homogeneously along their tangent vector are studied by Brownian dynamics simulations. Systems in two dimensions are investigated, corresponding to filaments adsorbed to interfaces or surfaces. A large…
Highly periodic structures are often said to convey the beauty of nature. However, most material properties are strongly influenced by the defects they contain. On the mesoscopic scale, molecular self-assembly exemplifies this interplay;…
We experimentally study the formation of surface patterns in grafted hydrogel films of nanometer-to-micrometer thicknesses during imbibition-driven swelling followed by evaporation-driven shrinking. Creases are known to form at the hydrogel…
Here we report a facile method to generate a high density of point defects in graphene on metal foil and show how the point defects affect the electronic structures of graphene layers. Our scanning tunneling microscopy (STM) measurements,…
Several groups have reported spontaneous formation of periodic pillar-like arrays in molten polymer nanofilms confined within closely spaced substrates maintained at different temperatures. These formations have been attributed to a…
We present a two-dimensional theoretical model for the slow chemical corrosion of a thin film of a disordered solid by suitable etching solutions. This model explain different experimental results showing that the corrosion stops…
We report the first successful simulation of spontaneous formation of surface magnetic structures from a large-scale dynamo by strongly-stratified thermal convection in Cartesian geometry. The large-scale dynamo observed in our…