The Mechanism of High-Temperature Superconductivity with a Pinch of Iron

It has long been conjectured that the unusual magnetic excitation spectrum of the cuprate high-temperature superconductors play an important role in the mechanism for superconductivity. I argue that the remarkable number of similarities in the excitation spectra of novel iron based high-temperature superconductors must mean that the same mechanism is at play. Through neutron spectroscopy measurements on iron tuned Fe1+yTe0.7Se0.3 we discover development of an hourglass dispersion above Tc and opening of a spin gap below Tc [1]. We conclude the hourglass is a necessary – but not sufficient – requisite for superconductivity. Based on this insight we propose a guide line for discovering new families of high-temperature superconductors. References [1] N. Tsyrulin et al., Magnetic hourglass dispersion and its relation to high-temperature superconductivity in iron-tuned Fe1+yTe0.7Se0.3, New Journal of Physics 14, 073025 (2012)