Physicists utilized ice to generate a swirling electric field.

To create a smooth and precise transition between two layers of the same substance or different materials, researchers typically synthesize bilayer materials directly, one on top of the other. However, this method does not allow for precise control over the angle of rotation of the layers relative to each other, especially for small angles.

Professor Ly Thuc Hue's team developed an innovative technique for moving monolayers using ice. This method has proven to be a key element in achieving a high-quality boundary between layers of molybdenum disulfide, MoS₂. Compared to other techniques, this method is more efficient, less time-consuming, and more cost-effective. The laboratory holds an active patent for this method.

Prior to this research, generating a vortex electric field required expensive thin-film deposition technologies and complex procedures. Now, physicists have demonstrated that the desired effect can be achieved by rotating the layers of two-dimensional materials relative to each other. The study has been published in the journal Science.

The formation of a vortex electric field in rotated layers of molybdenum disulfide has allowed scientists to create a two-dimensional quasicrystal. Quasicrystals are molecular structures with crystalline properties that lack short-range order. Atoms in a quasicrystal are ordered, but the arrangement of atoms and molecules repeats at distances greater than the size of the molecules. Quasicrystals can exhibit types of internal symmetry that are impossible in ordinary crystals, and they have low thermal and electrical conductivity. Quasicrystals are used as high-strength coatings and materials in spintronics and quantum electronics.

Using ice, researchers were able to create structures with rotation angles ranging from zero to 60 degrees. Bilayer molybdenum disulfide possesses rotational symmetry of 12th order—the structure repeats itself upon a 30-degree rotation.

The vortex electric field varies depending on the angle of rotation of the layers relative to each other and can be used to establish a more stable method of information storage for electronic devices, as well as to study optical effects related to light polarization, including rapid polarization switching. Physicists believe that materials with a vortex electric field will be valuable in quantum computing, spintronics, and nanotechnology.