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Collective Modes in High-Temperature Superconductors

T. Dahm·D. Manske·L. Tewordt
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Abstract

The role of collective modes in various experiments on the cuprates is investigated. We calculate the neutron scattering, photoemission (ARPES), and Raman scattering intensities below $T_c$ within the fluctuation-exchange (FLEX) approximation for the two-dimensional Hubbard model. It is shown that the large peak in the dynamical spin susceptibility arises from a weakly damped spin-density-wave collective mode. This gives rise to a dip between the sharp low energy peak and the higher binding energy hump in the ARPES spectrum. Furthermore, we show that the collective mode of the amplitude fluctuation of the d-wave gap yields a broad peak above the pair-breaking threshold in the $B_{1g}$ Raman spectrum.

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T. Dahm, D. Manske, L. Tewordt. 1998-08-19. Collective Modes in High-Temperature Superconductors. https://doi.org/10.1103/physrevb.58.12454

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