Disappearance of superconductivity due to vanishing coupling in the overdoped Bi$$_{2}$$ 2 Sr$$_{2}$$ 2 CaCu$$_{2}$$ 2 O$$_{8+\delta }$$ 8+δ

Abstract

The pairing mechanism of cuprate superconductors is still under debate. Here, Valla et al. report that mass renormalization in Bi$$_{2}$$ 2 Sr$$_{2}$$ 2 CaCu$$_{2}$$ 2 O$$_{8+\delta }$$ 8+δ weakens with doping and disappears precisely where superconductivity disappears, eliminating phononic mechanism for pairing.