Simulating anti-skyrmions on a lattice.

Area of Science:

• Condensed Matter Physics
• Materials Science
• Spintronics

Background:

• Magnetic skyrmions are topologically non-trivial spin textures with potential applications in data storage and neuromorphic computing.
• Research has predominantly focused on skyrmions, neglecting their counterparts, anti-skyrmions, which possess opposite topological charge.

Purpose of the Study:

• To investigate the interactions supporting the stabilization of anti-skyrmions.
• To explore the conditions for the existence of Bloch and Néel type skyrmions and anti-skyrmions.
• To characterize the phase diagram and properties of anti-skyrmion structures.

Main Methods:

• Utilized Monte Carlo simulations on spin-lattice systems.
• Employed a three-dimensional spin lattice model.
• Analyzed the effects of ferromagnetic exchange and Dzyaloshinskii-Moriya (DM) interactions.

Main Results:

• Identified that a combination of ferromagnetic exchange and DM interactions stabilizes skyrmions and anti-skyrmions.
• Determined that the specific structure of DM interactions dictates the type of spin texture formed.
• Established a finite-temperature phase diagram for a 3D spin lattice model, revealing a stable anti-skyrmion lattice phase over a wide temperature range.
• Investigated the creation/annihilation dynamics of anti-skyrmion tubes and the influence of DM interaction strength on their size.

Conclusions:

• The Dzyaloshinskii-Moriya interaction is crucial for stabilizing anti-skyrmions, alongside ferromagnetic exchange.
• Anti-skyrmions can form stable lattice phases at finite temperatures, expanding the landscape of topological spin textures.
• This work provides fundamental insights into the behavior and control of anti-skyrmions, paving the way for future spintronic device applications.