2018/04/04 by Mykola Dvornik, Johan Åkerman, Dvornik, Mykola +1 · 1 citation
Engineering · Physics and Astronomy · #FOS: Physical sciences #Magnetic properties of thin films #Magneto-Optical Properties and Applications #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Theoretical and Computational Physics #cond-mat.mes-hall
paper · pdf · doi:10.48550/arxiv.1804.01585
5 pages, 3 figures
arxiv created 2018/04/04 · openalex publication_date 2018/04/04 · arxiv updated 2018/04/06 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Nonlinearity of magneto-dynamics is typically described by a single constant, N, with positive and negative values indicating repulsion and attraction of magnons, respectively. In thin magnetic films with easy-plane magnetic anisotropy, magnon attraction is typically achieved for an in-plane magnetization. At sufficient stimulus, e.g. via application of spin transfer torque, the attraction can give rise to self-localized magnetic solitons, such as spin wave bullets, which shrink as their amplitude increases. In contrast, for an oblique magnetization above a certain critical angle, the repulsion of magnons only allows for propagating modes, which expand when pumped more strongly. Here we demonstrate, both analytically and using micromagnetic simulations, that such a dichotomic description is inadequate for magnonic edge modes, which naturally appear in confined magnetic systems. In particular, we demonstrate that the confinement potential of such modes is nonlinear in nature and its contribution makes N non-monotonically dependent on their amplitude. As a prominent example, edge modes show compression and expansion for negative and positive N, yet remain localized. In striking contrast to the extended geometries, edge magnons might also repeal even for an in-plane magnetization.