A new window has opened into the strange world that forms when ultra thin materials are stacked and rotated by only a degree or two. When scientists twist two sheets of a magnetic material called CrI3, the result is not a minor adjustment in structure but the creation of an entirely new magnetic landscape. What first appears to be a simple alignment trick turns into a powerful method for reshaping magnetism itself, unlocking patterns and behaviors that have never been seen in two dimensional materials.
CrI3 is already unusual. It is one of a handful of crystals that remain magnetic even when shaved down to the thickness of a few atoms. When two bilayers are placed on top of each other and rotated, the overlapping lattices form repeating patterns known as moiré structures. These patterns act like an invisible scaffold that rearranges how electrons and spins behave. In many twisted systems, moiré patterns determine everything from conductivity to the appearance of new phases of matter. But in this case, something even stranger happens.
Instead of forming magnetic structures that match the size of the underlying moiré pattern, the twisted crystal generates magnetic textures that grow far beyond the expected scale. These textures are not small. In the most striking samples, magnetic structures stretch hundreds of nanometers across, up to ten times larger than the repeating pattern beneath them. These oversized features form a second, much larger ordering pattern. It behaves as if the material is enforcing its own set of rules that override the geometry of the stack. Researchers call these enormous patterns super moiré textures, and they reveal an unexpected ability for twisted magnets to reorganize themselves.
The idea that the material would ignore the scale of its own underlying pattern was not a prediction. Standard thinking held that magnetic regions should shrink as the twist angle grows, since a larger twist creates a smaller moiré pattern. Instead, the magnetic structures expand. At certain angles, the material gathers magnetic regions together, merging small repeating units into extended patches that stretch across many moiré cells. The result is a magnetic landscape that looks nothing like the geometric template beneath it.
Inside these twisted crystals, ferromagnetic and antiferromagnetic regions compete for control. In some stacks, the two inner layers behave differently from the two outer layers. The inner pair flips between ferromagnetic and antiferromagnetic alignments depending on how the lattice overlaps. The outer layers tend to prefer antiferromagnetic coupling. Combined with strong intralayer interactions, the system becomes a battleground of competing forces. At larger twist angles, all of these competing regions are pushed tightly together, and the magnetic order stops following the repeating moiré boundaries.
Instead of clean, cell sized domains, the twist forces the magnetic boundaries to smear, bend, and stretch. Domain walls widen far beyond what is expected. In samples rotated by about one degree, the transition zones between magnetic regions can reach more than one hundred nanometers across. These broad boundaries signal that spins are tilting, canting, and arranging themselves in complex ways. The simple picture of up and down magnetization breaks down, replaced by swirling arrangements that hint at more exotic structures.
Measurements of the magnetic field above these samples reveal faint but coherent textures hidden inside the broader magnetic regions. When the background field from the main domains is removed, what remains is a delicate, repeating pattern with a surprising level of order. These patterns form hexagonal arrangements that stretch hundreds of nanometers. Even more unusual, the size of these textures grows as the moiré wavelength shrinks, creating an inverse relationship between the underlying lattice pattern and the emerging magnetic structure.
In the most revealing tests, the material is cooled under strong magnetic fields. This sets the system into a more ordered state, forcing spins to settle into stable configurations. Under these conditions, the antiferromagnetic regions of the twisted crystal reveal dot like formations arranged in a regular pattern. These dots are not defects or noise. They are signatures of localized whirling spin structures known as skyrmions.
Skyrmions behave like tiny magnetic vortices. Their spins twist from upward at the edge to downward at the center, or the opposite, forming a stable, topologically protected structure. In this material, the observed features match a specific class known as Néel skyrmions. These are typically associated with systems that include strong Dzyaloshinskii Moriya interactions, a type of spin orbit coupling that forces spins to tilt relative to each other rather than align head on.
The twisted CrI3 stack provides exactly the right ingredients. The nearby hBN layers and the twist induced environment break certain symmetries, introducing interactions that tilt spins and stabilize vortex like formations. The skyrmions that appear here are small, around sixty nanometers, but they sit inside a much larger super moiré lattice that organizes them into repeating hexagonal arrangements.
These skyrmion patterns remain stable even when the sample is warmed. Measurements taken at 4, 25, and 35 kelvin show that the repeating structure survives temperature changes that would typically wash out delicate magnetic order. Even when the overall magnetic contrast decreases, the pattern becomes clearer as the system approaches its critical temperature. This stability is notable because skyrmions usually require very specific conditions to survive. Seeing them persist across such a wide temperature range signals that the twisted geometry provides an unusually robust environment.
The presence of skyrmions helps explain several puzzling results that earlier optical measurements hinted at but could not directly resolve. Optical methods observed strong signals that suggested nonuniform magnetism across twisted samples, but without spatial resolution there was no way to confirm the underlying structure. Direct imaging fills this gap and confirms that the twisted crystal naturally produces vortex like spin structures at small twist angles.
The combined behavior of these twisted layers challenges long held assumptions about low dimensional magnets. Traditionally, stable long range magnetic order in two dimensional systems requires strong magnetic anisotropy. This usually suppresses the complex spin twisting needed to support skyrmion formation. Yet in the twisted system, long range order and topological spin structures appear together. The twist introduces a new form of magnetic competition that allows both to coexist. Magnetic anisotropy remains active, but the moiré environment modulates the exchange forces and spin interactions enough to support noncollinear textures.
The implications reach far beyond CrI3. Many other two dimensional magnets share similar structural properties. Materials such as CrCl3, CrBr3, CrSBr, and Fe5GeTe2 host a wide range of magnetic interactions. Adding controlled twist angles to these systems could unlock entirely new magnetic phases with tunable textures. The ability to create stable skyrmions and large scale magnetic patterns with simple rotation may offer a new pathway toward magnetic memory devices, low power computing elements, and other technologies that rely on manipulating spin textures.
What makes this system so compelling is that a small mechanical adjustment changes the entire magnetic environment. A twist of less than two degrees transforms a straightforward magnetic crystal into a playground of competing interactions, extended domains, and vortex like features. At certain angles, the system organizes itself into patterns that are far larger than the repeating structure beneath it. At other angles, the magnetic contrast fades completely, showing that only a narrow window produces these emergent textures.
This tunability allows researchers to build a kind of magnetic phase diagram controlled by twist angle. At very small angles, the moiré pattern dominates. At intermediate angles, super moiré textures rise. At larger angles, the competing forces flatten out, leaving almost uniform magnetization. This progression highlights how sensitive two dimensional materials are to geometry. Tiny adjustments in alignment are enough to reshape the collective behavior of thousands of atoms.
The discovery of super moiré magnetism and skyrmions in twisted CrI3 adds a new branch to the growing field of twist engineered materials. Similar breakthroughs in twisted graphene and other two dimensional systems have already revealed superconductivity, correlated insulating phases, and topological behavior that do not appear in untwisted structures. Now magnetism joins that list, showing that rotation can unlock entirely new magnetic phenomena.
The work demonstrates that the moiré effect is not only a geometric curiosity but a powerful tool for designing magnetic states that do not exist in nature. It also shows that magnets at the atomic scale do not always follow intuitive patterns. When layered, twisted, and placed under the right conditions, they can form extended, self organizing structures that defy simple models.
The magnetic textures discovered here are among the largest ever seen in twisted magnets, and the appearance of skyrmions adds a new dimension to the field. These results show that the frontier of two dimensional magnetism is far from settled. Twisted crystals continue to reveal hidden behaviors waiting to be uncovered, and each new discovery opens another path toward controlling magnetism with a level of precision that once seemed impossible.
Source:
Nature Nanotechnology. Super moiré spin textures in twisted two dimensional antiferromagnets. https://doi.org/10.1038/s41565-025-02103-y
