The spin resonance and high frequency optical properties of the cuprates

TL;DR

This paper links the superconductivity-induced blue shift of plasma frequency in cuprates to changes in the spin resonance, showing consistency with spectral weight and temperature dependence.

Contribution

It provides a theoretical explanation connecting optical properties to spin resonance phenomena in cuprate superconductors.

Findings

Blue shift of plasma frequency correlates with spin resonance development.

Magnitude of shift matches the small spectral weight of the resonance.

Temperature dependence of the shift follows the spin resonance peak.

Abstract

We argue that recently observed superconductivity-induced blue shift of the plasma frequency $\delta \omega_{pl}$ in $Bi_2Sr_2CaCu_2O_{8+\delta}$ is related to the change in the integrated dynamical structure factor associated with the development of the spin resonance below $T_c$. We show that the magnitude of $\delta \omega_{pl}$ is consistent with the small integrated spectral weight of the resonance, and its temperature dependences closely follow that of the spin resonance peak.