Theory of the Resonant Neutron Scattering of High $T_c$ Superconductors

TL;DR

This paper provides a theoretical explanation for a sharp spectral peak observed in neutron scattering experiments on high-temperature superconductors, linking it to a new collective mode in the Hubbard model that informs about the superconducting gap symmetry.

Contribution

It introduces a novel collective mode in the Hubbard model to explain experimental neutron scattering results in high $T_c$ superconductors.

Findings

Identification of a new collective mode in the Hubbard model.

Explanation of the spectral peak at 41 meV in neutron scattering.

Insights into the symmetry of the superconducting gap.

Abstract

Recent polarized neutron scattering experiments on $YBa_2 Cu_3 O_7$ have revealed a sharp spectral peak at the $(\pi,\pi)$ in reciprocal lattice centered around the energy transfer of $41\ meV$. We offer a theoretical explanation of this remarkable experiment in terms of a new collective mode in the particle particle channel of the Hubbard model. This collective mode yields valuable information about the symmetry of the superconducting gap.