Topological Aspects of Solitons in Ferromagnets

• 来源期刊: 理论物理通讯（英文版）
• 年，卷（期）: 2008,（9）
• 页码范围: 777-780
• 页数: 4页
• 语种: 英文

摘要

Two kinds of topological soliton (skyrmion and magnetic vortex ring) in ferromagnets are studied.They have the common topological origin,a tensor Hαβ=→/n·(θα→/n×θβ→/n),which describes the non-trivial distribution of local orientation of magnetization →/n at large distances in space.The topological stability of skyrmion is protected by the winding number.Knot-like topological defect as magnetic vortex rings is also studied.On the assumption that magnetic vortex rings are geometric lines,we present their &function distribution in ferromagnetic materials.Furthermore,it is briefly shown that Hopf invariant is a proper topological invariant to describe the topology of magnetic vortex rings.