Phys.org July 1, 2024
Topological insulators are known to exist in one (wire), two (sheet) and three (cube) dimensions; all with different possible applications in electronic devices. An international team of researchers (the Netherlands, China, Sweden) discovered that topological insulators may also exist at 1.58 dimensions, and that these could be used for energy-efficient information processing. They demonstrated that topological edge and corner modes arise in fractals formed upon depositing thin layers of bismuth on an indium antimonide substrate. Their scanning tunnelling microscopy results and theoretical calculations revealed the appearance and stability of nearly zero-energy modes at the corners of Sierpiński triangles, as well as the formation of outer and inner edge modes at higher energies. According to the researchers their work opens the perspective to extend electronic device applications in real materials at non-integer dimensions with robust and protected topological states… read more. TECHNICAL ARTICLE
Fractal Bi monolayers on InSb substrate. Credit: Nature Physics, 01 July 2024