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

TL;DR

This study explores the relationship between the superconducting gap energy and the two-magnon Raman peak energy in Bi2Sr2Ca{1-x}YxCu2O{8+eta}, revealing how magnetic excitations relate to superconductivity across doping levels.

Contribution

It establishes a quantitative link between the two-magnon peak energy and the superconducting gap energy, highlighting the role of magnetic excitations in superconductivity in cuprates.

Findings

The B1g scattering intensity is depleted below the two-magnon peak energy in underdoped samples.

The depletion region decreases as the two-magnon peak energy decreases with increased carrier concentration.

The superconducting gap energy is approximately proportional to the two-magnon peak energy, with a factor of 0.34-0.41.

Abstract

The relation between the electronic excitation and the magnetic excitation for the superconductivity in Bi2Sr2Ca{1-x}YxCu2O{8+\delta} 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 $2\Delta \approx \alpha \hbar \omega_{\rm Two-Magnon} \approx J_{\rm effective}$ $(\alpha=0.34-0.41)$ from under to overdoping hole concentration.