Tunable Creation and Annihilation of Magnetic Bimerons in Square-Shaped Submicron Dot

Recently, the study of nontrivial topological spin textures has gained immense attention due to their fascinating properties such as stability, small size, topological protection, and low drive current density. Magnetic bimeron is one such topological spin texture that has been realized experimentally and theoretically in the past few years. A magnetic bimeron is defined as the topological counterpart of skyrmions in in-plane magnetized systems. In this work, using micromagnetic simulations, we stabilize bimerons in a square-shaped submicrometer dot with in-plane magnetic anisotropy. We first investigate the effect of interfacial Dzyaloshinskii-Moriya interaction (IDMI) on the magnetization reversal mechanism by analyzing the snapshots of the spin configuration and total energy of the system. Our results indicate a monotonic increase in coercive field values and total energy with increasing DMI values (D) from 0 to 3 mJ/m(2). However, for D = 4 mJ/m(2), we see the stabilization of bimerons of both of the topological charges (Q = +1 and Q = -1) in the square dot during the magnetization reversal process. We also report that the formation of a bimeron (Q = +1) or an antibimeron (Q = -1) during the reversal can be controlled by the application of a static bias field in addition to the sweeping field. Furthermore, we show the dynamical conversion of a chiral stripe domain into pairs of bimeron and antibimeron in the presence of Zhang-Li type of spin-transfer torque. The results presented in this work will be useful in building future spintronic-based devices where bimerons can be used as bits of information carriers.