Phase-field simulation of strain-induced ferroelectric domain evolution in hexagonal manganites

The domain structures evolution induced by strain in hexagonal manganites was simulated through using phase-field simulation. The result demonstrated that tensile strain in x direction (or compressive strain in y direction) and pure shear strain will drive topological ferroelectric vortex into topological stripe domains in y direction and x direction, respectively. During this ferroelectric domain evolution, the annihilation of topological vortex-antivortex was found in a way that vortices and antivortices are moving in the opposite direction. Meanwhile, the topological charge is conservative during this evolution under the periodic boundary condition.