Domain-wall orientation in antiferromagnets controlled by magnetoelastic effects

Abstract

In this paper, we develop the mathematical framework to describe the physical phenomenon behind the equilibrium configuration joining two antiferromagnetic domains. We firstly define the total energy of the system and deduce the governing equations by minimizing it with respect to the field variables. Then, we solve the resulting system of nonlinear PDEs together with proper initial and boundary conditions by varying the orientation of the 90$^{\circ}$ domain wall (DW) configuration along the sample. Finally, the angular dependence of elastic and magnetoelastic energies as well as of incompatibility-driven volume effects is computed.