The first version of this story appeared in the middle Quant Magazine.
In 2024, superconductivity—the flow of electricity with zero resistance—was discovered in three different materials. Two situations extend the book’s understanding of the incident. The third one completely dismantled it. “It’s a very rare form of superconductivity that many people would have thought was impossible,” said Ashvin Vishwanath, a physicist at Harvard University who was not involved in the discovery.
Since 1911, when Dutch scientist Heike Kamerlingh Onnes first observed the disappearance of electrical resistance, superconductivity has fascinated physicists. There is a pure mystery as to how it happens: This process requires electrons, which carry electrical energy, to pair up. Electrons repel each other, so how can they bond?
And then there’s the promise of technology: Already, the high efficiency has enabled the development of MRI machines and high-energy particle collisions. If physicists can fully understand how and when this phenomenon occurs, perhaps they can create a wire that conducts electricity more under everyday conditions than only at low temperatures, as is the case now. World-changing technologies—lossless power grids, magnetically driven cars—could follow.
Recent discoveries have unraveled the mystery of superconductivity and raised hopes. “It seems that, in materials, that high efficiency is everywhere,” said Matthew Yankowitz, a physicist at the University of Washington.
Findings from the latest revolution in materials science: All three new states of superconductivity come from devices assembled from flat sheets of atoms. These things show unprecedented flexibility; at the touch of a button, physicists can switch between conductance, repulsion, and abnormal behavior—a modern form of alchemy that has made the hunt for optimum performance very expensive.
Now it seems that it is possible that various causes can cause this condition. Just as birds, bees and dragonflies all fly using different wings, physical objects seem to pair electrons together in different ways. Even if the researchers are debating exactly what happens to the various two-dimensional materials in question, they expect that the growing zoo of superconductors will help them reach a universal view of the attraction.
Pairing electrons
The case for Kamerlingh Onnes’s observations (and the high performance observed in other cold metals) was finally cracked in 1957. John Bardeen, Leon Cooper, and John Robert Schrieffer discovered that at low temperatures, the jittery atomic lattice is quiet, and more. serious consequences are coming. The electrons gently attract the protons in the lattice, pulling them inward to create an excess positive charge. That transition, known as a phonon, can attract a second electron, forming a “Cooper pair.” Cooper pairs can all combine into a unified quantum entity in a way that a single election cannot. The resulting quantum soup slides without friction between the material atoms, which normally prevent the flow of electricity.
Bardeen, Cooper, and Schrieffer’s theory of phonon-based superconductivity earned them the physics Nobel Prize in 1972. But that wasn’t the whole story. In the 1980s, physicists discovered that copper-rich crystals called cuprates behaved well at high temperatures, where the atoms jiggle and bathe the phonons. Other similar examples followed.