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arXiv · cond-mat/9712255

Collective Excitations in High-Temperature Superconductors

M. I. Salkola·J. R. Schrieffer
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Abstract

Collective, low-energy excitations in quasi-two-dimensional d-wave superconductors are analyzed. While the long-range Coulomb interaction shifts the charge-density-wave and phase modes up to the plasma energy, the spin-density-wave excitation that arises due to a strong local electron-electron repulsion can propagate as a damped collective mode within the superconducting energy gap. It is suggested that these excitations are relevant to high-Tc superconductors, close to the antiferromagnetic phase boundary, and may explain some of the exotic features of the experimentally observed spectral-density and neutron-scattering data.

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M. I. Salkola, J. R. Schrieffer. 1997-12-20. Collective Excitations in High-Temperature Superconductors. https://doi.org/10.1103/physrevb.58.r5944

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