Discovery of a pair density wave state in a monolayer high-Tc iron-based superconductor

Understand

The pair density wave (PDW) is an extraordinary superconducting state where Cooper pairs carry nonzero momentum.

• It can emerge when the full condensation of zero momentum Cooper pairs is frustrated.
• Evidence for the existence of intrinsic PDW order in high-temperature (high-Tc) cuprate superconductors and kagome superconductors has emerged recently.
• However, the PDW order in iron-based high-Tc superconductors has not been observed experimentally.