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arXiv · cond-mat/9912232

Relation between the superconducting gap energy and the two-magnon Raman peak energy in Bi2Sr2Ca{1-x}YxCu2O{8+δ}

S. Sugai·T. Hosokawa
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Abstract

The relation between the electronic excitation and the magnetic excitation for the superconductivity in Bi2Sr2Ca{1-x}YxCu2O{8+δ} was investigated by wide-energy Raman spectroscopy. In the underdoping region the B1g scattering intensity is depleted below the two-magnon peak energy due to the "hot spots" effects. The depleted region decreases according to the decrease of the two-magnon peak energy, as the carrier concentration ncreases. This two-magnon peak energy also determines the B1g superconducting gap energy as $2Δ\approx α\hbar ω_{\rm Two-Magnon} \approx J_{\rm effective}$ $(α=0.34-0.41)$ from under to overdoping hole concentration.

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S. Sugai, T. Hosokawa. 1999-12-14. Relation between the superconducting gap energy and the two-magnon Raman peak energy in Bi2Sr2Ca{1-x}YxCu2O{8+δ}. https://doi.org/10.1103/physrevlett.85.1112

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