Confinement effects in dendritic growth

We study the interplay between crystal orientation and confinement in diffusion-limited growth. Growth of the overall morphology in the direction of minimal surface stiffness has been investigated in some detail by various authors, the most recent advances being summarized by Brener et al (Brener E, Muller-Krumbhaar H and Temkin D 1996 Phys. Rev. E 54 2714). Here, we consider competing influences, each trying to impose a different growth direction. The simplest possible situation giving rise to such a competition is growth in a channel with a mismatch between the orientation of the channel walls and surface tension anisotropy. Analysing this situation, we find a new structure and gain further insight into the problem of morphological stability. Another case is that of periodic boundary conditions, where the same angle of misorientation can be used to describe growth of a tilted array of finger-shaped crystals. It is found that the transition between dendritic and doublonic structures is affected by the rift.