Spin-wave interference in magnetic vortex stacks

Precise probing spin wave mode frequencies in the vortex state of circular magnetic dots

magnetic dots A. A. Awad, K. Y. Guslienko, J. F. Sierra, G. N. Kakazei, V. Metlushko, and F. G. Aliev Dpto. Física de la Materia Condensada, CIII, Universidad Autónoma de Madrid, 28049 Madrid, Spain Dpto. Fisica de Materiales, Universidad del Pais Vasco, 20018 Donostia-San Sebastian, Spain IKERBASQUE, The Basque Foundation for Science, 48011 Bilbao, Spain Departamento de Fisica da Faculdade de ...

Spin-wave modes in magnetic nanowires

Spin-wave excitation in magnetic insulators by spin-transfer torque.

We study the excitation of spin waves in magnetic insulators by the current-induced spin-transfer torque. We predict preferential excitation of surface spin waves induced by an easy-axis surface anisotropy with critical current inversely proportional to the penetration depth and surface anisotropy. The surface modes strongly reduce the critical current and enhance the excitation power of the cu...

Spin-wave interference in three-dimensional rolled-up ferromagnetic microtubes.

We have investigated spin-wave excitations in rolled-up Permalloy microtubes using microwave absorption spectroscopy. We find a series of quantized azimuthal modes which arise from the constructive interference of Damon-Eshbach-type spin waves propagating around the circumference of the microtubes, forming a spin-wave resonator. The mode spectrum can be tailored by the tube's radius and number ...

Magnetic vortex-antivortex crystals generated by spin-polarized current

We study vortex pattern formation in thin ferromagnetic films under the action of strong spin-polarized currents. Considering the currents which are polarized along the normal of the film plane, we determine the critical current above which the film goes to a saturated state with all magnetic moments being perpendicular to the film plane. We show that stable square vortex-antivortex superlattic...