Evolution of solitons in the PbTiO3/SrTiO3 multilayer film driven by the electric field

Abstract

Polar topologies constitute of a great platform for designing and developing new high-density electronic memories. Exploring their evolutionary processes with the applied electric field is of great significance to understand and regulate novel topological domain structures. Here, phase field simulations were used to study the evolution processes of the PbTiO₃/SrTiO₃ multilayer film with different thicknesses under the applied electric field. The electric field-thickness phase diagram of the multilayer film was constructed, paying special attention to the electric field range of the solitons, as well as their densities during the application of the electric field in multilayer film of different thicknesses. When the electric field is withdrawn, the density of solitons remains constant, manifesting the non-volatility or topological protection of these topological structures. The phase diagram for zero-electric-field solitons reveals that these solitons can persist over a significantly broader electric field range. Quenching under the finite external field, skyrmions can be obtained at a lower electric field. These results may have guiding significance for designing and developing next-generation nanoelectronic devices based on topological structures.