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arXiv · 1112.2725

Relationship among superconductivity, pseudogap, and high-energy magnetic fluctuations in a model high-Tc superconductor from electronic Raman scattering

Yuan Li·M. Le Tacon·M. Bakr·D. Terrade·D. Manske·R. Hackl·L. Ji·M. K. Chan·N. Barisic·X. Zhao·M. Greven·B. Keimer
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Abstract

We use electronic Raman scattering to study the model single-layer cuprate superconductor HgBa2CuO4+d. In an overdoped sample, we observe a pronounced amplitude enhancement of a high-energy peak related to two-magnon excitations in insulating cuprates upon cooling below the critical temperature Tc. This effect is accompanied by the appearance of the superconducting gap and a pairing peak above the gap in the Raman spectrum, and it can be understood as a consequence of feedback of the Cooper pairing interaction on the high-energy magnetic fluctuations. All of these effects occur already above Tc in two underdoped samples, demonstrating a related feedback mechanism associated with the pseudogap.

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Yuan Li, M. Le Tacon, M. Bakr, D. Terrade, D. Manske, R. Hackl, L. Ji, M. K. Chan, N. Barisic, X. Zhao, M. Greven, B. Keimer. 2011-12-12. Relationship among superconductivity, pseudogap, and high-energy magnetic fluctuations in a model high-Tc superconductor from electronic Raman scattering. https://doi.org/10.1103/physrevlett.108.227003

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