Physicists find two quantum states competing in cuprates

A team led by Canada's INRS used laser pulses to briefly suppress superconductivity in a copper-oxide crystal and tracked electron energies over trillionths of a second. The pseudogap appears to compete with superconductivity for electrons rather than enable it, though signatures of both states can briefly coexist.

• Laser pulses disrupted superconductivity in a cuprate for trillionths of a second
• Suppressing superconductivity produced a pseudogap-like signature in the energy spectrum
• The signature appeared below the superconducting transition temperature, ruling out heating
• Features of both states could briefly coexist