Soft-magnetic skyrmions induced by surface-state coupling in an intrinsic ferromagnetic topological insulator sandwich structure

Abstract

A magnetic skyrmion induced on a ferromagnetic topological insulator (TI) is a real-space manifestation of the chiral spin texture in the momentum space, and can be a carrier for information processing by manipulating it in tailored structures. Here, we fabricate a sandwich structure containing two layers of a self-assembled ferromagnetic septuple-layer TI, Mn(Bi${}_{1-x}$Sb${}_x$)${}_2$Te${}_4$ (MnBST), separated by quintuple layers of TI, (Bi${}_{1-x}$Sb${}_x$)${}_2$Te${}_3$ (BST), and observe skyrmions through the topological Hall effect in an intrinsic magnetic topological insulator for the first time. The thickness of BST spacer layer is crucial in controlling the coupling between the gapped topological surface states in the two MnBST layers to stabilize the skyrmion formation. The homogeneous, highly-ordered arrangement of the Mn atoms in the septuple-layer MnBST leads to a strong exchange interaction therein, which makes the skyrmions "soft magnetic". This would open an avenue towards a topologically robust rewritable magnetic memory.

References in corpus (28)

• Anomalous Hall effect
• Experimental Observation of the Quantum Anomalous Hall Effect in a Magnetic Topological Insulator
• Topological Field Theory of Time-Reversal Invariant Insulators
• Quantized Anomalous Hall Effect in Magnetic Topological Insulators
• Magnetic-field-induced quantized anomalous Hall effect in intrinsic magnetic topological insulator MnBi${}_2$Te${}_4$
• Topological Hall effect in the A-phase of MnSi
• High-precision realization of robust quantum anomalous Hall state in a hard ferromagnetic topological insulator
• Experimental realization of an intrinsic magnetic topological insulator
• Unique thickness-dependent properties of the van der Waals interlayer antiferromagnet $\mathrm{MnB}{\mathrm{i}}_2\mathrm{T}{\mathrm{e}}_4$ films
• Magnetic impurities on the surface of a topological insulator
• Interface-driven topological Hall effect in SrRuO${}_3$-SrIrO${}_3$ bilayer
• Unusual Hall Effect Anomaly in MnSi Under Pressure
• Robust formation of skyrmions and topological Hall effect in epitaxial thin films of MnSi
• Intrinsic magnetic topological insulator phases in the Sb doped MnBi2Te4 bulks and thin flakes
• Carrier-independent ferromagnetism and giant anomalous Hall effect in magnetic topological insulator
• Electrically controllable surface magnetism on the surface of topological insulator
• Highly-ordered wide bandgap materials for quantized anomalous Hall and magnetoelectric effects
• Variety of magnetic topological phases in the (MnBi${}_2$Te${}_4$)(Bi${}_2$Te${}_3$)${}_m$ family
• Electric-field control of anomalous and topological Hall effects in oxide bilayer thin films
• Rational design principles of quantum anomalous Hall effect from superlattice-like magnetic topological insulators
• Large-gap magnetic topological heterostructure formed by subsurface incorporation of a ferromagnetic layer
• Dimensional Crossover Induced Topological Hall Effect in a Magnetic Topological Insulator
• Concurrence of Quantum Anomalous Hall and Topological Hall Effects in Magnetic Topological Insulator Sandwich Heterostructures
• Berry phase engineering at oxide interfaces
• Domain wall of a ferromagnet on a three-dimensional topological insulator
• Topological Hall Effect in a Topological Insulator Interfaced with a Magnetic Insulator
• Coexistence of surface and bulk ferromagnetism mimics skyrmion Hall effect in a topological insulator
• Controlled creation of nanometric skyrmions using external magnetic fields

Cited by in corpus (1)

• Intrinsic magnetic topological insulators of the MnBi${}_2$Te${}_4$ family