Dipolar-stabilized first and second-order antiskyrmions in ferrimagnetic multilayers.

Area of Science:

• Condensed Matter Physics
• Materials Science
• Spintronics

Background:

• Skyrmions and antiskyrmions are topologically protected spin structures with opposite vorticities.
• Antiskyrmions were previously confined to materials with D2d symmetry.
• These magnetic quasi-particles hold potential for spintronic devices.

Purpose of the Study:

• To demonstrate the stabilization of antiskyrmions by magnetic dipole-dipole interaction in Fe/Gd-based multilayers.
• To investigate the co-existence of antiskyrmions with other spin textures like Bloch skyrmions and type-2 bubbles.
• To determine the material property and magnetic field ranges for the formation and dissipation of these spin objects.

Main Methods:

• Lorentz transmission electron microscopy (LTEM) for direct imaging of spin structures.
• Fabrication of Fe/Gd-based multilayers with inserted Ir layers to tune magnetic properties.
• Micromagnetic simulations to analyze the stabilization mechanisms and system dynamics.

Main Results:

• Observation of first and second-order antiskyrmions stabilized by magnetic dipole-dipole interaction.
• Coexistence of antiskyrmions, Bloch skyrmions, and type-2 bubbles in the studied multilayers.
• Identification of ranges for material properties and magnetic fields governing the formation and dissipation of diverse spin objects.

Conclusions:

• Reduction in saturation magnetization and uniaxial magnetic anisotropy promotes the formation of various spin objects.
• Dipolar interaction is the primary stabilizing force for the observed antiskyrmions and other spin textures.
• This work broadens the material platform for antiskyrmion research and spintronic applications.