Strong-coupling Effects in cuprate High-$T_{c}$ Superconductors by magnetooptical studies

TL;DR

This study uses magneto-optical techniques to investigate the role of magnetic excitations in the strong coupling phenomena observed in high-temperature cuprate superconductors, specifically YBCO.

Contribution

It provides direct comparison of infrared and neutron scattering data to evaluate magnetic contributions to superconductivity in YBCO.

Findings

Magnetic resonance depression observed under magnetic field.

Magneto-optical data correlates with neutron scattering results.

Magnetic excitations are significant in strong coupling effects.

Abstract

Signatures of strong coupling effects in cuprate high-$T_{c}$ superconductors have been authenticated through a variety of spectroscopic probes. However, the microscopic nature of relevant excitations has not been agreed upon. Here we report on magneto-optical studies of the CuO$_{2}$ plane carrier dynamics in a prototypical high-$T_{c}$ superconductor YBa$%_{2} $Cu$_{3}$O$_{y}$ (YBCO). Infrared data are directly compared with earlier inelastic neutron scattering results by Dai \textit{et al}. [Nature (London) \textbf{406}, 965 (2000)] revealing a characteristic depression of the magnetic resonance in H $\parallel $ \textit{c} field less than 7 T. This analysis has allowed us to critically assess the role of magnetic degrees of freedom in producing strong coupling effects for YBCO system.