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

摘要

Signatures of strong coupling effects in cuprate high-$T_{c}$ superconductorshave been authenticated through a variety of spectroscopic probes. However, themicroscopic nature of relevant excitations has not been agreed upon. Here wereport on magneto-optical studies of the CuO$_{2}$ plane carrier dynamics in aprototypical high-$T_{c}$ superconductor YBa$%_{2} $Cu$_{3}$O$_{y}$ (YBCO).Infrared data are directly compared with earlier inelastic neutron scatteringresults 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 criticallyassess the role of magnetic degrees of freedom in producing strong couplingeffects for YBCO system.