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arXiv · 1802.08007

Dependence of $T_c$ on the $q-ω$ structure of the spin-fluctuation spectrum

Thomas Dahm·D. J. Scalapino
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Abstract

A phenomenological spin-fluctuation analysis (Ref. 1), based upon inelastic neutron scattering (INS) and angular resolved photoemission spectroscopy (ARPES) data for ${\rm YBCO}_{6.6}(T_c=61K)$, is used to calculate the functional derivative of the d-wave eigenvalue $λ_d$ of the linearized gap equation with respect to the imaginary part of the spin susceptibility $χ''(q,ω)$ at 70K. For temperatures near $T_c$, the variation of $T_c$ with respect to $χ''(q,ω)$ is proportional to this functional derivative. Based on this, we discuss how different parts of the $q$ and $ω$ dependent spin-fluctuation spectrum of YBCO$_{6.6}$ contribute to $T_c$.

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Thomas Dahm, D. J. Scalapino. 2018-02-22. Dependence of $T_c$ on the $q-ω$ structure of the spin-fluctuation spectrum. https://doi.org/10.1103/physrevb.97.184504

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