Magnetic topological insulators change phase under pressure

In 2019, researchers discovered that two intrinsically magnetic materials, MnBi₂Te₄ and MnBi₂Te₇, can behave as topological insulators – materials that are electrically insulating in bulk, but conduct electricity well on the surface. A team led by Yangpeng Qi from ShanghaiTech University has now demonstrated that it is possible to induce phase transitions in these layered heterostructures by applying high pressures to them, thereby tuning their crystal structure and electronic properties. The results could further our understanding of the interplay between magnetism and topology in these and related materials, they say.