Orientational transitions in four-row magnetic-dipole lattices

Square lattices with four rows of dipoles have been considered. It has been shown that, if there are several stable equilibrium configurations, an external field excites transitions that change the direction of the dipole moments of one of the lattice rows. Orientational transitions in the structure that consists of intersecting perpendicular lattices have been studied. It has been found that the front of the orientational transition that results in a configuration with rows having alternating directions passes through the region of the intersection of the lattices into the other part of the lattice. The front of the other orientational transitions stops in the region of the intersection. The effect of an external field on certain dipoles located in the region of the intersection makes it possible to control the movement of the orientational-transition front; i.e., the front can be forced to pass through the region of the intersection in the initial direction; its direction can be changed, the configuration of the orientational transition can be changed or the front can be stopped in the region of the intersection.