Time-Resolved X-ray Microscopy of Spin-Torque-Induced Magnetic Vortex Gyration

Abstract

Time-resolved X-ray microscopy is used to image the influence of alternating high-density currents on the magnetization dynamics of ferromagnetic vortices. Spin-torque induced vortex gyration is observed in micrometer-sized permalloy squares. The phases of the gyration in structures with different chirality are compared to an analytical model and micromagnetic simulations, considering both alternating spinpolarized currents and the current's Oersted field. In our case the driving force due to spin-transfer torque is about 70% of the total excitation while the remainder originates from the current's Oersted field. This finding has implications to magnetic storage devices using spin-torque driven magnetization switching and domain-wall motion.

10 pages, 3 figures

References in corpus (10)

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• Electrical switching of vortex core in a magnetic disk
• Magnetic Vortex Resonance in Patterned Ferromagnetic Dots
• Current-driven resonant excitation of magnetic vortex
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• Current-induced magnetic vortex core switching in a Permalloy nanodisk
• Vortex polarity switching by a spin--polarized current
• Harmonic oscillator model for current- and field-driven magnetic vortices
• Current-Driven Domain-Wall Dynamics in Curved Ferromagnetic Nanowires

Cited by in corpus (29)

• Dynamics of coupled vortices in a pair of ferromagnetic disks
• Universal criterion and phase diagram for switching a magnetic vortex core in soft magnetic nanodots
• Current-induced torques in textured Rashba ferromagnets
• Tunable energy transfer between dipolar-coupled magnetic disks by stimulated vortex gyration
• Switching magnetic vortex core by a single nanosecond current pulse
• Few-nm tracking of magnetic vortex orbits and their decay with ultrafast Lorentz microscopy
• Spin-transfer mechanism for magnon-drag thermopower
• Time-resolved x-ray microscopy for materials science
• Current-driven and field-driven domain walls at nonzero temperature
• Enhanced Non-Adiabaticity in Vortex Cores due to the Emergent Hall Effect
• Electric spectroscopy of vortex states and dynamics in magnetic disks
• Dynamics of Vortex Nucleation in Nanomagnets with Broken Symmetry
• Proposal of a robust measurement scheme for the non-adiabatic spin torque using the displacement of magnetic vortices
• Reversal process of a magnetic vortex core under the combined action of a perpendicular field and spin transfer torque
• Spin-Transfer Torque Induced Vortex Dynamics in Fe/Ag/Fe Nanopillars
• X-ray imaging of spin currents and magnetisation dynamics at the nanoscale
• Low-amplitude magnetic vortex core reversal by non-linear interference between azimuthal spin waves and the vortex gyromode
• Spin motive forces due to magnetic vortices and domain walls
• Electrical rectification effect in single domain magnetic microstrips: a micromagnetics-based analysis
• Resonant pinning spectroscopy with spin-vortex pairs
• Skyrmion Dynamics and Transverse Mobility: Skyrmion Hall Angle Reversal on 2D Periodic Substrates with dc and Biharmonic ac Drives
• Current-Induced Resonant Motion of a Magnetic Vortex Core: Effect of Nonadiabatic Spin Torque
• Off-centered immobile magnetic vortex under influence of spin-transfer torque
• Large amplitude vortex gyration in Permalloy/Bi${}_2$Se${}_3$-like heterostructures
• Transient dynamics of strongly coupled spin vortex pairs: effects of anharmonicity and resonant excitation on inertial switching
• Static and dynamic properties of vortex pairs in asymmetric nanomagnets
• Detection of domain wall eigenfrequency in infinity-shaped magnetic nanostructures
• Magneto-Optical Spectrum Analyzer
• Probing the spin polarization of current by soft X-ray imaging of current-induced magnetic vortex dynamics