Superconductors could one day help power a new generation of ultra-efficient electronics, but major technical obstacles have kept the technology largely confined to the laboratory. Now, scientists at Sweden’s Chalmers University of Technology have developed a new approach to one of the field’s biggest challenges: sustaining superconductivity at high temperatures while withstanding strong magnetic fields.
This advance could bring superconducting technology closer to practical applications in electronics, energy systems, and quantum devices.
Modern digital devices, data centers, and information and communication technology (ICT) networks account for an estimated 6-12% of global electricity consumption. As energy demand continues to increase, researchers are looking for ways to significantly increase the efficiency of electronics.
Superconductors are particularly attractive because they can conduct electrical current without energy loss. Unlike traditional electronic systems, which waste energy as heat, superconductors can transfer electricity without resistance. In theory, this could make power grids, electronics, and quantum technologies hundreds of times more efficient.
Why are superconductors difficult to use?
Despite their promise, superconductors face several obstacles that limit their real-world applications.
One of the challenges is temperature. Many superconductors only work at extremely low temperatures, often around minus 200 degrees Celsius. Reaching and maintaining such temperatures requires complex and energy-intensive cooling systems.
Magnetic fields pose another big problem. Strong magnetic fields can weaken or even eliminate superconductivity. This is especially important because many advanced electronic systems and quantum technologies generate or rely on magnetic fields.
For superconducting materials to be commercialized and widely used, they must be able to operate at high temperatures (ideally close to room temperature) while remaining stable in strong magnetic environments.
Another strategy for achieving stronger superconductivity
Researchers have spent years improving superconductors by changing their chemical composition, but progress has been limited. The Chalmers team decided to take a different approach.
“By sculpting the surface on which the superconductor rests, we were able to induce superconductivity at significantly higher temperatures than previously possible. We also found that the material remains superconducting even when exposed to strong magnetic fields,” explains Floriana Lombardi, professor of quantum device physics at Chalmers University and lead author of the study published in 2006. nature communications.
How small surface changes made a big difference
The researchers worked with copper oxide materials from the cuprate family. Copper oxide is already known to exhibit superconductivity at relatively high temperatures, but its chemical structure is difficult to modify once it has been produced.
The superconducting layer used in the study was just a few nanometers thick, less than one millionth the thickness of a human hair. These ultrathin materials must be grown on a supporting base called a substrate, which acts as a template during manufacturing.
This breakthrough was achieved by applying nanoscale modifications to the substrate itself.
“The atoms in the substrate are arranged in a specific pattern, which allows us to ‘guide’ how the atoms settle in the superconducting layer. By changing the surface design of the substrate, we were able to influence the superconducting properties and ensure that they remain even when high temperatures and high magnetic fields are applied,” explains Erik Wahlberg, a researcher at Sweden’s RISE Institute.
Before adding the superconducting film, the researchers treated the substrates in a vacuum at high temperatures. This process created a regular pattern of small peaks and valleys across the surface.
These microscopic features changed the electronic environment where the substrate and superconducting layer were in contact, creating conditions favorable for stronger superconductivity.
“We were able to see how the properties of the electrons begin to take on a preferential orientation in this interfacial region, behaving in a way that stabilizes and strengthens the superconducting state,” Lombardi says.
New design principles for future superconductors
The results of this study introduce a new way of thinking about superconducting materials. Rather than focusing solely on discovering new materials or changing their chemistry, researchers may be able to improve performance by carefully designing the surfaces on which those materials grow.
“Instead of looking for entirely new materials or manipulating the chemical properties of existing materials, we are now showing how superconductivity can be enhanced by sculpting the substrate,” Lombardi says.
The researchers believe this strategy could eventually allow superconductors to function at much higher temperatures, even at temperatures approaching room temperature.
The research also points to future applications in energy-efficient electronics, advanced quantum components, and technologies that need to operate with strong magnetic fields.
“This shows that very small changes at the nanoscale can have a decisive impact and may even unlock the full potential of superconductivity in future electronics,” Lombardi says.
Research details
The research “Improving the superconductivity of ultrathin YBa2Cu3O7−δ films using nanofaceted substrates” was published in the journal. nature communications.
The authors are Eric Wahlberg, Riccardo Arpaia, Debmalya Chakraborty, Alexei Karabukhov, David Vigneault, Cyril Proust, Annika M. Black-Shafer, Thilo Borf, Götz Seibold, and Floriana Lombardi.
Researchers participating in the project are affiliated with Chalmers University of Technology, Sweden’s RISE Institute, Ca’ Foscari University in Venice (Italy), Birla Institute of Technology Pilani, KK Birla Goa Campus (India), Indian Institute of Science Education and Research (IISER), India, Uppsala University (Sweden), Grenoble-Alpes University, Toulouse University, INSA-T (France), and the Institute. Physics, BTU Cottbus Senftenberg, Germany.
Part of the research was conducted at Myfab Chalmers, a clean room facility.
Funding was provided by the Swedish Research Council (VR), the Knut and Alice Wallenberg Foundation, the European Union through an EIC Pathfinder grant, and the German Foundation.
