Quantum Tug-of-war Limits High-temperature Superconductivity - Quantum Zeitgeist

New work helps show why the dream of high-temperature superconductivity has been so hard to realize: a quantum brawl between superconductivity and a competing state of matter. The finding resulted from a collaboration that included theorists with the Simons Foundation's Flatiron Institute in New York City and experimentalists at Quebec's Institut national de la recherche scientifique (INRS). The researchers investigated a copper alloy called a 'cuprate' as it transitioned from the superconducting state to an enigmatic neighboring state of matter called the 'pseudogap.' Using laser pulses and computer simulations, they were able to understand the behavior of electrons inside the cuprate. In a paper published October 20 in Nature Physics , the team shows how the two states — superconductivity and the pseudogap — wrestle for dominance. That finding challenges the idea that superconductivity in cuprates merely builds upon a pre-existing pseudogap phase. "We're really showing that these states are competing," says study co-author Olivier Gingras , an associate research scientist at the Flatiron Institute's Center for Computational Quantum Physics (CCQ).

A research group led by scientists at the University of Illinois Urbana-Champaign has found compelling evidence of pair-density waves on the surface of uranium ditelluride. These structures persisted at temperatures higher than the superconducting transition temperature, ScienceAlert reports. The results were published in the journal PNAS. Electron pairs form patternsIn the superconducting state, electrons can form Cooper pairs and move through a material without electrical resistance or energy loss through heating. The existence of pair-density waves, or PDWs, was theoretically predicted as early as 2007. In this state, Cooper pairs form spatially repeating patterns resembling waves in sand. Uranium ditelluride enters a superconducting state at temperatures below approximately 2.1 kelvin, or about minus 271 degrees Celsius. The material also interests physicists as a possible rare spin-triplet superconductor: in such a system, paired electrons also have a small magnetic orientation. More current news is available on the UA. News Telegram channel Telegram. Observations of magnetic field and temperatureSigns of PDW had previously been recorded in uranium ditelluride.

Governments’ borrowing costs are being pulled in opposite directions