Antiferromagnetic Half-skyrmions and Bimerons at room temperature

Abstract

In the quest for post-CMOS technologies, ferromagnetic skyrmions and their anti-particles have shown great promise as topologically protected solitonic information carriers in memory-in-logic or neuromorphic devices. However, the presence of dipolar fields in ferromagnets, restricting the formation of ultra-small topological textures, and the deleterious skyrmion Hall effect when driven by spin torques have thus far inhibited their practical implementations. Antiferromagnetic analogues, which are predicted to demonstrate relativistic dynamics, fast deflection-free motion and size scaling have recently come into intense focus, but their experimental realizations in natural antiferromagnetic systems are yet to emerge. Here, we demonstrate a family of topological antiferromagnetic spin-textures in $\alpha$-Fe${}_2$O${}_3$ - an earth-abundant oxide insulator - capped with a Pt over-layer. By exploiting a first-order analogue of the Kibble-Zurek mechanism, we stabilize exotic merons-antimerons (half-skyrmions), and bimerons, which can be erased by magnetic fields and re-generated by temperature cycling. These structures have characteristic sizes of the order ~100 nm that can be chemically controlled via precise tuning of the exchange and anisotropy, with pathways to further scaling. Driven by current-based spin torques from the heavy-metal over-layer, some of these AFM textures could emerge as prime candidates for low-energy antiferromagnetic spintronics at room temperature.

18 pages, 4 figures

References in corpus (33)

• Antiferromagnetic spintronics
• Observation of room temperature magnetic skyrmions and their current-driven dynamics in ultrathin Co films
• Additive interfacial chiral interaction in multilayers for stabilization of small individual skyrmion at room temperature
• Skyrmions at room temperature : From magnetic thin films to magnetic multilayers
• Room temperature chiral magnetic skyrmion in ultrathin magnetic nanostructures
• Skyrmion Hall Effect Revealed by Direct Time-Resolved X-Ray Microscopy
• Skyrmion lattice with a giant topological Hall effect in a frustrated triangular-lattice magnet
• Tunable Room Temperature Magnetic Skyrmions in Ir/Fe/Co/Pt Multilayers
• Discovery of Magnetic Antiskyrmions Beyond Room Temperature in Tetragonal Heusler Materials
• Static and Dynamical Properties of Antiferromagnetic Skyrmions in the Presence of Applied Current and Temperature
• Electrically controlled long-distance spin transport through an antiferromagnetic insulator
• Magnetic bilayer-skyrmions without skyrmion Hall effect
• Skyrmion-electronics: Writing, deleting, reading and processing magnetic skyrmions toward spintronic applications
• The 2020 Skyrmionics Roadmap
• Full phase diagram of isolated skyrmions in a ferromagnet
• Antiferromagnetic domain wall motion driven by spin-orbit torques
• Magnetic bimerons as skyrmion analogues in in-plane magnets
• Current-Driven Skyrmion Dynamics and Drive-Dependent Skyrmion Hall Effect in an Ultrathin Film
• Electrical Switching of Tristate Antiferromagnetic Néel Order in $\alpha$-Fe${}_2$O${}_3$ Epitaxial Films
• Diameter-independent skyrmion Hall angle in the plastic flow regime observed in chiral magnetic multilayers
• Current-Induced Dynamics and Chaos of Antiferromagnetic Bimerons
• Bound states of skyrmions and merons near the Lifshitz point
• Observation of magnetic vortex pairs at room temperature in a planar α-Fe2O3/Co heterostructure
• Quantitative Study on Current-Induced Effect in an Antiferromagnet Insulator/Pt Bilayer Film
• Pinning and movement of individual nanoscale magnetic skyrmions via defects
• Asymmetric isolated skyrmions in polar magnets with easy-plane anisotropy
• Stability and lifetime of antiferromagnetic skyrmions
• Bimeron Clusters in Chiral Antiferromagnets
• Ultrafast generation and dynamics of isolated skyrmions in antiferromagnetic insulators
• Magnetic skyrmions in confined geometries : effect of the magnetic field and the disorder
• Coherent magneto-elastic domains in multiferroic BiFeO3 films
• Magnetic vortex as a ground state for micron-scale antiferromagnetic samples
• Micromagnetic modelling and imaging of vortex|merons structures in an oxide|metal heterostructure

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• Topological Transformation and Free-Space Transport of Photonic Hopfions
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• Topologically controlled multiskyrmions in photonic gradient-index lenses
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• Anisotropic Dzyaloshinskii-Moriya interaction and topological magnetism in two-dimensional magnets protected by P4-m2 crystal symmetry
• Long-distance propagation of high-velocity antiferromagnetic spin waves
• Spontaneous antiferromagnetic skyrmion/antiskyrmion lattice and spiral spin liquid states in the frustrated triangular lattice
• Anisotropic Dzyaloshinskii-Moriya interaction protected by D2d crystal symmetry in two-dimensional ternary compounds
• Homochiral antiferromagnetic merons, antimerons and bimerons realized in synthetic antiferromagnets
• Dzyaloshinskii-Moriya interaction and magnetic skyrmions induced by curvature
• Emergence of zero-field non-synthetic single and interchanged antiferromagnetic skyrmions in thin films
• Antiferromagnetic insulatronics: spintronics in insulating 3d metal oxides with antiferromagnetic coupling
• Photonic torons, topological phase transition and tunable spin monopoles
• Skyrmion fluid and bimeron glass protected by a chiral spin liquid on a kagome lattice
• Giant 2D Skyrmion Topological Hall Effect with Ultrawide Temperature Window and Low-Current Manipulation in 2D Room-Temperature Ferromagnetic Crystals
• Machine learning techniques to construct detailed phase diagrams for skyrmion systems
• Stability of skyrmion crystal phase in antiferromagnetic triangular lattice with DMI and single-ion anisotropy
• Role of substrate clamping on anisotropy and domain structure in the canted antiferromagnet $\alpha$-Fe${}_2$O${}_3$
• Revealing the Altermagnetism in Hematite via XMCD Imaging and Anomalous Hall Electrical Transport
• Distinct moiré textures of in-plane electric polarizations for distinguishing moiré origins in homobilayers
• Strong and tunable magnetoelectric coupling in 2D trilayer heterostructures
• Nonreciprocal dynamics of ferrimagnetic bimerons
• Topological orbital Hall effect caused by skyrmions and antiferromagnetic skyrmions
• Imaging antiferromagnetic domain fluctuations and the effect of atomic-scale disorder in a doped spin-orbit Mott insulator
• Bimerons create bimerons: proliferation and aggregation induced by currents and magnetic fields
• Imprint from ferromagnetic skyrmions in an antiferromagnet via exchange bias
• Spatially reconfigurable topological textures in freestanding antiferromagnetic nanomembranes
• X-ray Linear Dichroic Tomography of Crystallographic and Topological Defects
• All-electrical detection of skyrmion lattice state and chiral surface twists
• Frustration-induced magnetic bimerons in transition metal halide CoX2 (X = Cl, Br) monolayers
• Spin-Current Instability at a Magnetic Domain Wall in a Ferromagnetic Superfluid: a Generation Mechanism of Eccentric Fractional Skyrmions
• Skyrmionics in correlated oxides
• Meron configurations in easy-plane chiral magnets
• A spin model for intrinsic antiferromagnetic skyrmions on a triangular lattice
• Topological invariants of vortices, merons, skyrmions, and their combinations in continuous and discrete systems
• Magnetic Bimeron Traveling on the Domain Wall
• A route towards stable homochiral topological textures in A-type antiferromagnets
• Significant Unconventional Anomalous Hall Effect in Heavy Metal/Antiferromagnetic Insulator Heterostructures
• Topological meron-antimeron domain walls and skyrmions in a low-symmetry system
• Spatial Antiferromagnetic Spin Texture as a Nano-Oscillator
• Magnetic bubble crystal in tetragonal magnets
• Road to zero-field antiferromagnetic skyrmions in a frustrated AFM/FM heterostructure
• Noncollinear antiferromagnetic textures driven high harmonic generation from magnetic dynamics in the absence of spin-orbit coupling
• Tailoring energy barriers of Bloch-point-mediated transitions between topological spin textures
• Frustration-driven topological textures on the honeycomb lattice: antiferromagnetic meron-antimeron and skyrmion crystals emerging from spiral spin liquids
• Zero Field Antiferromagnetically Coupled Skyrmions and their Field-Driven Uncoupling in Composite Chiral Multilayers
• Antiferromagnetic nanoscale bit arrays of magnetoelectric Cr${}_2$O${}_3$ thin films
• Antiferromagnetic droplet soliton driven by spin current
• Anisotropic Field Suppression of Morin Transition Temperature in Epitaxially Grown Hematite Thin Films
• Anomalous magnetoresistance in an antiferromagnetic Kagome semimetal heterostructures
• Chaotic spin precession in antiferromagnetic domain walls
• Topological spin Hall effect in antiferromagnets driven by vector Néel chirality
• Interaction and collision of skyrmions in chiral antiferromagnets
• Vortex propagation and phase transitions in a chiral antiferromagnetic nanostripe
• Emergent topological quasiparticle kinetics in constricted nanomagnets
• Moiré spintronics: Emergent phenomena, material realization and machine learning accelerating discovery
• Skyrmion-deriven topological spin and charge Hall effects in diffusive antiferromagnetic thin films
• Strain-driven domain wall network with chiral junctions in an antiferromagnet
• Stacking-dependent nonreciprocal transport in magnetic skyrmions
• Charge ordering and spontaneous topological Hall effect in bilayer skyrmion crystals