Nonlinear nano-scale localized breather modes in a discrete weak ferromagnetic spin lattice

作者：Kavitha L^*; Parasuraman E; Gopi D; Prabhu A; Vicencio Rodrigo A

来源：Journal of Magnetism and Magnetic Materials, 2016, 401: 394-405.

DOI：10.1016/j.jmmm.2015.10.021

• Soliton
• Exchange interactions
• Localized modes
• Spin dynamics

We investigate the propagation dynamics of highly localized discrete breather modes in a weak ferromagnetic spin lattice with on-site easy axis anisotropy due to crystal field effect. We derive the discrete nonlinear equation of motion by employing boson mappings and p-representation. We explore the onset of modulational instability both analytically in the framework of linear stability analysis and numerically by means of molecular dynamics (MD) simulations, and a perfect agreement was demonstrated. It is also explored that how the antisymmetric nature of the canted ferromagnetic lattice supports highly localized discrete breather (DBs) modes as shown in the stability/instability windows. The energy exchange between low amplitude discrete breathers favours the growth of higher amplitude DBs, resulting eventually in the formation of few long-lived high amplitude DBs.

• 出版日期2016-3-1