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Two Distinct Electronic Contributions in the Fully Symmetric Raman Response of High $T_{c}$ Cuprates

M. Le Tacon·A. Sacuto·D. Colson
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Abstract

We show by non resonant effect in HgBa$_2$CuO$_{4+δ}$ (Hg-1201)and by Zn substitutions in YBa$_2$Cu$_3$O$_{7-δ}$ (Y-123) compounds that the fully symmetric Raman spectrum has two distinct electronic contributions. The A$_{1g}$ response consists in the superconducting pair breaking peak at the 2$Δ$ energy and a collective mode close to the magnetic resonance energy. These experimental results reconcile the \textit{d-wave} model to the A$_{1g}$ Raman response function in so far as a collective mode that is distinct from the pair breaking peak is present in the A$_{1g}$ channel.

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M. Le Tacon, A. Sacuto, D. Colson. 2005-02-11. Two Distinct Electronic Contributions in the Fully Symmetric Raman Response of High $T_{c}$ Cuprates. https://doi.org/10.1103/physrevb.71.100504

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