Symmetry is a key concept in our understanding of the physical world around us. They way self-similar components are arranged following the guidelines of symmetry dictates their joint behavior. It is no accident that the human body evolved in a mirror-symmetric shape, as beautifully captured by Da Vinci’s work. Similarly, in material science, certain symmetries dictate the functionality of a material on the quantum level. A recent focus point in the field is to understand how certain symmetries work together to give fundamentally new responses in so-called topological materials. These materials display distinct surface and bulk properties, making them promising candidates for future application in quantum electronics.
Ever since the discovery of the quantum Hall effect (Nobel Prize 1985), symmetry has been the guiding principle in the search for topological materials. Now an international team of researchers from Germany, Switzerland, and the USA has introduced an alternative guiding principle, ‘quasi-symmetry’, which leads to the discovery of a new type of topological material with great potential for applications in spintronics and quantum technologies. This work has been published in Nature Physics.