Topological spin crystals by itinerant frustration

Area of Science:

• Condensed Matter Physics
• Materials Science
• Spintronics

Background:

• Topological spin textures like vortices and skyrmions exhibit unique magnetic, transport, and optical properties.
• Conventional topological spin textures often rely on specific material symmetries (noncentrosymmetric systems).

Purpose of the Study:

• To review and explain the stabilization mechanisms of a new class of topological spin textures in itinerant magnets.
• To highlight the role of itinerant frustration in stabilizing these textures, particularly in centrosymmetric systems.

Main Methods:

• Focus on the interplay between charge and spin degrees of freedom in itinerant electron systems.
• Analysis of electron-mediated interactions, including bilinear and biquadratic spin interactions in momentum space.

Main Results:

• Itinerant frustration is identified as the key mechanism for stabilizing topological spin crystals.
• Demonstration of stabilization for unconventional skyrmion crystals (high skyrmion number), meron crystals, and hedgehog crystals.
• Identification of momentum-space spin interactions as crucial for itinerant frustration.

Conclusions:

• Itinerant frustration offers a unified understanding of unconventional topological spin crystals in itinerant magnets.
• This perspective encourages further research into novel topological phenomena within these materials.