A material made from yttrium, barium and copper oxide (better known as YBCO) has intrigued scientists since its discovery in 1987, largely because it retains its superconductive properties at a higher-than-normal temperature. However, it is extremely brittle, which makes it tricky to put to practical use.

But researchers can still learn much from it. For instance, its unusual properties can provide insight into designing possible room-temperature superconductors —that is, materials that conduct electricity with no resistance at room temperature. Doing so would have a huge impact on power transmission, medical imaging and fusion reactor magnets.

One thing about YBCO that has mystified researchers is that doping it with praseodymium, a rare earth element, completely kills the material’s superconductive properties. That is unusual because adding other rare earth elements to YBCO does not have the same effect.