Two-body problem of core-region coupled magnetic vortex stacks

Abstract

The dynamics of all four combinations of possible polarity and circularity states in a stack of two vortices is investigated by time-resolved scanning transmission x-ray microscopy. The vortex stacks are excited by unidirectional magnetic fields leading to a collective oscillation. Four different modes are observed that depend on the relative polarizations and circularities of the stacks. They are excited to a driven oscillation. We observe a repulsive and attractive interaction of the vortex cores depending on their relative polarizations. The nonlinearity of this core interaction results in different trajectories that describe a two-body problem.

Transient dynamics of strongly coupled spin vortex pairs: Effects of anharmonicity and resonant excitation on inertial switching

“…Several multi-vortex systems have been explored for use in oscillators, including lateral vortex arrays [17] and vertically stacked vortex pairs. [18] Pairing of vortices can give rise to dynamic properties qualitatively different from those of the individual vortices constituting the pair, as has been shown in recent studies on lateral exchange-coupled vortex pairs [19] as well as vertical magnetostatically-coupled symmetric [20] and asymmetric [21,22] vortex pairs. The precise nature of the collective dynamics of a vortex pair depends on the strength of the inter-vortex interactions as well as the exact core/chirality configuration within the pair.…”

Realizing Corner States in Artificial Crystals Based on Topological Spin Textures

“…On the other hand, the topological phase of magnetic materials is of great current interest in magnetism because of its fundamen-tal significance as well as in spintronics because of its practical utility for robust information processing [25][26][27][28][29][30][31][32]. A particularly interesting system is magnetic texture-based metamaterials since they can offer flexible controllability that can benefit from modern spintronic techniques [33][34][35][36][37][38][39][40][41]. Indeed, topological chiral edge states have been predicted in a twodimensional honeycomb lattice of magnetic textures (such as vortices and skyrmions) [42,43]; however, these states are first-order by nature, according to the classification of topological insulators.…”

Resonant pinning spectroscopy with spin-vortex pairs

“…17 A related memory idea based on resonantly depinning vortex-like domainwalls in a nanowire, the so-called race-track memory, was demonstrated to efficiently switch under spin-torque current excitation. 18 A number of recent studies focused on lateral exchange-coupled vortex pairs 19 and magnetostaticallycoupled vortex arrays [20][21][22][23][24] as well as on vertical vortex pairs [25][26][27] have shown that the inter-vortex coupling can significantly alter the vortex-pair dynamics, giving rise to new resonant modes of motion, not present in the isolated vortex case. We have previously shown that in the limit of strong core-core coupling in a vertical stack, with a monopole-like interaction of the two cores, the collec- Resistance versus in-plane field for a SAF magnetic junction in the parallel-core antiparallel-chirality (P-AP) vortex pair state.…”