Nanoscale Redesign Boosts Superconductivity at Higher Temperatures

Researchers at Chalmers University of Technology in Sweden have developed a new method to enhance superconductivity. They found that subtly sculpting the surface beneath an ultrathin superconducting material allows it to maintain superconductivity at higher temperatures and under stronger magnetic fields. This advance addresses a major challenge in moving superconducting technologies from laboratories to practical applications.

Superconductors can transmit electrical current with no energy loss. This property could make electronic devices, power grids, and quantum technologies more efficient. Current digital devices and information and communications technology (ICT) networks consume a significant portion of global electricity. Superconductors offer a path to reduce this energy consumption.

However, superconductors typically require extremely low temperatures, often around minus 200 degrees Celsius. They also lose their superconducting properties in strong magnetic fields. These limitations necessitate complex cooling systems and restrict their use in many advanced electronic systems that generate or rely on magnetic fields.

The Chalmers team focused on modifying the substrate, the supporting foundation for the superconducting material. They used a copper-oxide material from the cuprate family, known for relatively high-temperature superconductivity. The superconducting layer was only a few nanometers thick. By treating the substrate in a vacuum at high temperatures, they created an orderly pattern of microscopic ridges and valleys. These features guided the atomic arrangement of the superconducting layer, preserving its properties at higher temperatures and in strong magnetic fields.

This approach suggests a new design principle for future superconductors. Instead of solely altering chemical composition, researchers can engineer the surfaces on which these materials are grown. This strategy could enable superconductors to function at much higher temperatures, potentially closer to room temperature. The findings could lead to more energy-efficient electronics, advanced quantum components, and technologies operating in strong magnetic fields.

The study, titled “Boosting superconductivity in ultrathin YBa2Cu3O7−δ films via nanofaceted substrates,” was published in the journal *Nature Communications*. Researchers from Chalmers University of Technology, RISE Research Institutes of Sweden, and other international institutions contributed to the project. Funding was provided by the Swedish Research Council, the Knut and Alice Wallenberg Foundation, and the European Union.