Effects of external magnetic field and magnetic anisotropy on chiral spin structures of square nanodisks investigated with a quantum simulation approach. (April 2016)

• Record Type: Journal Article
• Authors: Liu, Zhaosen; Ian, Hou
• Is Part Of: Superlattices and microstructures. Volume 92(2016)
• Page Start: 174
• Page End: 180
• Publication Date: 2016-04
• Subjects: Dzyaloshinsky-Moriya interaction -- Magnetic vortex -- Computational algorithm -- Quantum theory; Superlattices as materials -- Periodicals; Microstructure -- Periodicals; Semiconductors -- Periodicals; Superréseaux -- Périodiques; Microstructure (Physique) -- Périodiques; Semiconducteurs -- Périodiques; 621.38152
• DOI: 10.1016/j.spmi.2016.02.028
• Languages: English
• ISSNs: 0749-6036

Abstract

Abstract: We employed a quantum simulation approach to investigate the magnetic properties of monolayer square nanodisks with Dzyaloshinsky-Moriya (DM) interaction. The computational program converged very quickly, and generated chiral spin structures on the disk planes with good symmetry. When the DM interaction is sufficiently strong, multi-domain structures appears, their sizes or average distance between each pair of domains can be approximately described by a modified grid theory. We further found that the external magnetic field and uniaxial magnetic anisotropy both normal to the disk plane lead to reductions of the total free energy and total energy of the nanosystems, thus are able to stabilize and/or induce the vortical structures, however, the chirality of the vortex is still determined by the sign of the DM interaction parameter. Moreover, the geometric shape of the nanodisk affects the spin configuration on the disk plane as well. Highlights: Our new simulation approach was applied to FM nanodisks with DM interaction. The chiralites of the calculated magnetic vortices are determined by DM interaction. The chiralities of the calculated magnetic vortices agree with experimental findings. The average distance between nearing magnetic domains agrees with a gird theory. External magnetic field and uniaxial anisotropy are able to induce magnetic vortex.