Interfacial phase transitions in a far-from-equilibrium magnetic growth model

TL;DR

This paper investigates interfacial phase transitions in a three-dimensional nonequilibrium magnetic growth model, revealing complex localization-delocalization and growth mode transitions with detailed phase diagrams.

Contribution

It introduces a nonequilibrium magnetic growth model with competing surface fields and characterizes its interfacial phase transitions, including a wetting transition and a growth mode transition, in both finite and thermodynamic limits.

Findings

Identification of a localization-delocalization transition of the interface.

Discovery of a concave-convex transition in the growth interface.

Phase diagram with six main regions in the thermodynamic limit.

Abstract

The irreversible growth of a magnetic film with spins having two possible orientations is studied in three-dimensional confined geometries of size $L\times L\times M$, where $M\gg L$ is the growing direction. A competing situation with two opposite short range surface magnetic fields $H$ of the same magnitude is analyzed. Due to the antisymmetric condition considered, an interface between domains with spins having opposite orientations develops along the growing direction. Such an interface undergoes a localization-delocalization transition that is the precursor of a wetting transition in the thermodynamic limit, in qualitative agreement with observations performed under equilibrium conditions. However, in contrast to its equilibrium counterparts, the film also exhibits a growing interface that undergoes a concave-convex transition in the growth mode. The phase diagram on the $H$ versus $T$ plane is first obtained for a finite system, and exhibits eight different regions. Subsequently, the phase diagram corresponding to the thermodynamic limit is obtained by extrapolation. It is shown that in the latter only six regions remain. The relevant physical properties of all of these regions are discussed in detail.