New superconducting materials have been discovered

The original version of this story appeared in How much magazinee.

In 2024, superconductivity—the flow of electric current with zero resistance—was discovered in three distinct materials. Two cases expand the textbook understanding of the phenomenon. The third is completely off. “It’s an extremely unusual form of superconductivity that many people would have said is not possible,” he said. Ashwin Vishwanatha physicist at Harvard University who was not involved in the discoveries.

Since 1911, when Dutch scientist Heike Kamerlingh Onnes first saw electrical resistance disappear, superconductivity has captivated physicists. There is the pure mystery of how it happens: The phenomenon requires electrons, which carry electric current, to couple. Electrons repel each other, so how can they come together?

Then there is the technological promise: already, superconductivity has allowed the development of MRI machines and powerful particle colliders. If physicists could fully understand how and when the phenomenon arises, perhaps they could engineer a wire that superconducts electricity in everyday conditions rather than exclusively at low temperatures, as is currently the case. World-changing technologies—lossless power grids, magnetically levitating vehicles—could follow.

Recent discoveries have added to the mystery of superconductivity and increased optimism. “It seems to be, in materials, that superconductivity is everywhere,” he said Matthew Yankowitza physicist at the University of Washington.

The findings come from a recent revolution in materials science: All three new cases of superconductivity arise in devices assembled from sheets of atoms. These materials exhibit unprecedented flexibility; at the touch of a button, physicists can switch between conducting, insulating, and more exotic behaviors—a modern form of alchemy that has supercharged the hunt for superconductivity.

Now it seems more and more likely that different causes can give rise to the phenomenon. Just as birds, bees and dragonflies all fly with different wing structures, the materials seem to bind electrons in different ways. Even while the researchers debate exactly what happens in the various two-dimensional materials in question, they anticipate that the growing zoo of superconductors will help them obtain a more universal view of the seductive phenomenon.

Electron Pairing

The case of Kamerlingh Onnes observations (and the superconductivity seen in other extremely cold metals) was finally cracked in 1957. John Bardeen, Leon Cooper and John Robert Schrieffer. get it that at low temperatures, the nervous atomic lattice of a material calms down, so more delicate effects come. The electrons gently tug at the protons in the lattice, pulling them inward to create an excess of positive charge. This deformation, known as a phonon, can then attract a second electron, forming a “Cooper pair”. Cooper pairs can all come together into a coherent quantum entity in a way that lone elections cannot. The resulting quantum soup flows without friction between the material’s atoms, which normally prevent electrical flow.

Bardeen, Cooper and Schrieffer’s theory of phonon-based superconductivity won them the Nobel Prize in physics in 1972. But it turned out that wasn’t the whole story. In the 1980s, physicists found that copper-filled crystals called cuprates could superconduct at higher temperatures, where atomic jiggles washed out the phonons. Other similar examples follow.