Research success
Novel surface superconductivity discovered in topological material
"Our results open up impressive prospects for basic research and future technological applications, for example in the field of quantum computing," says Prof Dr Christian Hemker-Heß from the Wuppertal Chair of Condensed Matter - Experimental Solid State Physics.
Since its discovery over a hundred years ago, the phenomenon of superconductivity has fascinated researchers. A superconductor is a material that can conduct electricity completely without resistance if it becomes cold enough. Normally, when electricity flows, energy is lost in the form of heat, but in a superconductor, electricity simply flows without losing any energy. Superconductivity is essential for applications such as superconducting magnetic coils or quantum interferometers, which are used for highly sensitive magnetic field measurements (e.g. in MRI machines in hospitals).
Promising for new technologies
Another class of materials discovered much later are so-called topological solids. A topological material is a special material that has completely different properties on its surface than in its interior. This can mean, for example: Current can flow on the outside, but not on the inside. What is special is that the current flows robustly at the edges, i.e. it is not stopped, even if there is dirt, scratches or other interference. This makes topological materials very stable and promising for new technologies. Topological materials could be used in future quantum computers, for example.
For the first time, it has now been possible to combine both phenomena - superconductivity and topology - in one material. The scientists involved were able to show that platinum bismuth (PtBi₂) is not only superconducting, but that this superconductivity only occurs on the surface.
Milestone in materials research
"The results of the current research could have far-reaching consequences for quantum physics," says Christian Hemker-Heß. "Future research will show whether the superconductivity in platinum bismuth itself has topological properties."
The discovery in platinum bismuth marks an important milestone in materials research and offers exciting new insights into the interplay between superconductivity and topology.
Further information on the topic can be found on the website of the School of Mathematics and Natural Sciences.
Project participants
In addition to the University of Wuppertal, the international research team also includes the Leibniz Institute for Solid State and Materials Research Dresden, the Universidad Nacional de Cuyo in Bariloche, Argentina and the Bar Ilan University in Israel.