Signatures of strong coupling effects in cuprate high-Tc 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 CuO2 plane carrier dynamics in a prototypical high-Tc superconductor YBaCu3Oy (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 ∥ \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.
@article{arxiv.cond-mat/0511590,
title = {Strong-coupling Effects in cuprate High-$T_{c}$ Superconductors by magnetooptical studies},
author = {Y. S. Lee and Z. Q. Li and W. J. Padilla and S. V. Dordevic and C. C. Homes and Kouji Segawa and Yoichi Ando and D. N. Basov},
journal= {arXiv preprint arXiv:cond-mat/0511590},
year = {2009}
}