Neutron Scattering Studies of the Magnetic Fluctuations in YBa_2Cu_3O_{7-\delta}

TL;DR

This study uses neutron scattering to investigate magnetic fluctuations in YBa_2Cu_3O_{7-\delta} across various doping levels, revealing incommensurability and a broadened resonance at high temperatures, contributing to understanding high-temperature superconductivity.

Contribution

It provides new experimental data on spin fluctuations and incommensurability in YBa_2Cu_3O_{7-\delta} at different oxygen doping levels, especially above T_c.

Findings

Incommensurability observed at oxygen levels 6.6 and 6.7

Resonance exists at 6.6 doping but is broadened and less intense at high temperatures

Magnetic fluctuations vary with doping and temperature, informing superconductivity mechanisms

Abstract

Neutron scattering measurements have been made on the spin fluctuations in YBa_2Cu_3O_{7-\delta} for different oxygen doping levels. Incommensurability is clearly observed for oxygen concentrations of 6.6 and 6.7 and is suggested for the 6.93. Measurements of the resonance for the O_{6.6} concentration show that it exists in a broadened and less intense form at temperatures much higher than T_c.