Physicists from the Université de Sherbrooke’s Institut Quantique have identified the transition that could explain why copper oxides harbour such impressive superconductive power. Putting an end to a 20-year debate in the field, researchers have discovered that a mysterious quantum phase transition, known as a pseudogap, results in a significant drop in the number of conduction electrons available to form the pairs required for superconductivity.
The team suggests that what happens in that moment could likely explain why cuprates allow for superconductivity at much higher temperatures than other materials—halfway between absolute zero and ambient temperature.
Their work falls within an international initiative aiming to exploit superconductivity—electrical transmission without resistance in certain materials—to considerably increase the energetic performance of many technologies. Thus far, cuprates are the most promising material, but the research community has a formidable physics problem to solve: Understanding the mysterious pseudogap phase.
Using a magnetic field two million times more powerful than the Earth’s, the team of scientists succeeded in suppressing superconductivity in a sample of cuprates and in carefully examining the pseudogap phase at near absolute zero temperatures (-273 C). According to scientists, these new findings will significantly change the direction of future research and lead to a new understanding of the properties of superconductive materials.
Principal Investigator: Louis Taillefer