NEWSROOM

Ultrafast light pulses have given physicists fresh evidence on the pseudogap, the enigmatic quantum state that has clouded cuprate superconductors for nearly four decades. Using time- and angle-resolved photoemission spectroscopy, researchers suppressed superconductivity in a copper-based compound and watched the pseudogap appear in its place, then fade as superconductivity returned.

New research on cuprates reveals that superconductivity and the pseudogap state compete for dominance rather than the pseudogap serving as a precursor, a finding that challenges prevailing models of high-temperature superconductivity. Using laser pulses and angle-resolved photoemission spectroscopy on a copper alloy, combined with computer simulations, the team tracked how electrons behave as the material shifts between the two phases.