New superconductors can be built atom by atom, researchers show

The future of electronics will be based on new types of materials. Sometimes, however, the natural topology of atoms makes it difficult to create new physical effects. To address this problem, researchers at the University of Zurich have now successfully engineered superconductors one atom at a time, creating new states of matter.

What will the computer of the future look like? How will it work? The search for answers to these questions is a major driver of basic physics research. There are several possible scenarios, ranging from the further development of classical electronics to neuromorphic computing and quantum computers.

What all these approaches have in common is that they are based on new physical effects, some of which have so far only been predicted in theory. Researchers are going all out and using cutting-edge equipment in their search for new quantum materials that will allow them to create such effects. But what if there are no suitable materials found in nature?

New approach to superconductivity

In a recent study published in Physics of natureThe research team of Professor Titus Neupert of UZH, working closely with physicists at the Max Planck Institute of Microstructure Physics in Halle (Germany), presented a possible solution.

The researchers made the required materials themselves, one atom at a time. They are focusing on new types of superconductors, which are particularly attractive because they offer zero electrical resistance at low temperatures. Sometimes referred to as “ideal dimagnets,” superconductors are used in many quantum computers due to their extraordinary interactions with magnetic fields. Theoretical physicists have spent years researching and predicting various superconducting states. ‘However, only a small number have so far been conclusively demonstrated in materials,’ says Professor Neupert.

Two new types of superconductivity

In their collaboration, the UZH researchers predicted how atoms should be arranged to create a new superconducting phase, and the team in Germany then conducted experiments to implement the related topology.

Using a tunneling microscope, they moved and deposited atoms in the right place with atomic precision. The same method was also used to measure the magnetic and superconducting properties of the system. By depositing chromium atoms on the surface of the superconducting niobium, the researchers were able to create two new types of superconductivity. Similar methods had previously been used to manipulate metal atoms and molecules, but until now it has never been possible to make two-dimensional superconductors with this approach.

The results not only confirm the physicists’ theoretical predictions, but also give them reason to speculate about what other new states of matter could be created in this way and how they could be used in quantum computers of the future.