Scientists smash superconductor speed limit to probe Cooper pair depairing

A team from the Max Planck Institute, Shanghai Institute of Microsystem and Information Technology, ETH Zurich and Oxford built an optoelectronic circuit that outruns the quantum processes behind Cooper pair depairing in superconductors. NbN loses superconductivity abruptly at a threshold current, while YBCO loses it gradually, a difference attributed to their s-wave and d-wave gap symmetries. The findings were published in Nature Physics.

• Circuit outpaces quantum vortex motion by several orders of magnitude
• NbN loses superconductivity abruptly, YBCO gradually
• Difference traced to s-wave and d-wave gap symmetries
• Findings published in the journal Nature Physics