Researchers from Monash University have successfully captured images of tiny, swirling structures within an ultra-thin semiconductor, a discovery that could lead to the development of more energy-efficient electronic devices. Published in Science Advances, the study identifies structures called merons and antimerons—nanoscale "whirlpools" of electrical polarization—within a twisted layer of tungsten diselenide (WSe₂), a two-dimensional semiconductor. The team created a moiré superlattice by stacking two atom-thin layers of the material and twisting them by just 0.1 degrees, forming a repeating nanoscale pattern. Using high-resolution imaging techniques, they mapped how electrical polarization behaves within this structure, revealing a network of merons and antimerons. Merons and antimerons are topological structures, meaning they have unique properties that make them resistant to changes caused by small disturbances. These structures have previously been observed in thicker materials, such as oxides, but this study marks the first time they have been directly observed in an ultra-thin semiconductor. The discovery is significant because it opens the door to manipulating these structures in devices that are much thinner and potentially more energy-efficient than current technologies. A key part of the research was distinguishing between the effects of twisting the material and the effects of strain, which can alter the behavior of the semiconductor. By creating vector maps, the team was able to quantify how much each factor—twist and strain—contributed to the formation of the moiré superlattice. This distinction is crucial for future studies aiming to control and utilize these structures in electronic applications. The findings were supported by both theoretical modeling and large-scale simulations, which confirmed the presence of circulating polarization patterns consistent with merons and antimerons. The combination of experimental and theoretical approaches provided strong evidence for the discovery. Researchers hope this work will guide the development of new electronic devices that take advantage of these nanoscale structures, potentially leading to advances in low-energy computing and other technologies.