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Twist Angle Control Generates Large-Scale Skyrmions in Layered 2D Antiferromagnets Researchers from the University of Edinburgh and collaborators have discovered that slightly twisting atomically thin magnetic crystals can generate unexpectedly large magnetic structures known as skyrmions. The study, published in Nature Nanotechnology, focuses on twisted double bilayer chromium triiodide (CrI3), a two-dimensional antiferromagnetic material. While previous work in moiré engineering showed that small angular mismatches between stacked layers can dramatically alter electronic properties, magnetism was generally expected to follow the same small-scale moiré pattern created by the overlapping lattices. However, using scanning nitrogen-vacancy magnetometry, the team observed magnetic textures extending up to approximately 300 nanometers—around ten times larger than the underlying moiré wavelength. Surprisingly, the size of these magnetic textures did not simply increase as the twist angle decreased. Instead, the skyrmion-like structures reached their maximum size near a twist angle of 1.1 degrees and disappeared above about 2 degrees. This counterintuitive behavior indicates that the magnetism does not merely mirror the moiré pattern but emerges from a balance of competing interactions, including exchange coupling, magnetic anisotropy, and Dzyaloshinskii–Moriya interactions. Large-scale spin dynamics simulations confirmed the formation of extended Néel-type antiferromagnetic skyrmions spanning multiple moiré cells. The researchers describe this phenomenon as “super-moiré spin order,” emphasizing that small atomic-scale rotations can stabilize topological magnetic states across much larger distances. These findings have potential implications for spintronics, where skyrmions are valued for their stability, small size, and low energy requirements for manipulation. Because these structures can be generated simply by controlling the twist angle—without complex fabrication techniques or strong electric currents—the approach could provide a geometry-based pathway toward low-power, energy-efficient computing technologies beyond conventional CMOS systems. https://killbait.com/en/twist-angle-control-generates-large-scale-skyrmions-in-layered-2d-antiferromagnets/?redirpost=871bfbb9-fa80-49fb-9517-c12e1c6a494d