Magnetic excitations and phonons simultaneously studied by resonant inelastic x-ray scattering in optimally doped Bi1.5Pb0.55Sr1.6La0.4CuO6+δ

• Published in: Physical review. B, Condensed matter and materials physics Vol. 92; no. 6
• Main Authors: Peng, Y. Y., Hashimoto, M., Sala, M. Moretti, Amorese, A., Brookes, N. B., Dellea, G., Lee, W. -S., Minola, M., Schmitt, T., Yoshida, Y., Zhou, K. -J., Eisaki, H., Devereaux, T. P., Shen, Z. -X., Braicovich, L., Ghiringhelli, G.
• Format: Journal Article
• Language: English
• Published: United States American Physical Society (APS) 24-08-2015
• Subjects: PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
• ISSN: 1098-0121; 1550-235X
• DOI: 10.1103/PhysRevB.92.064517

In this paper, magnetic excitations in the optimally doped high-Tc superconductor Bi1.5Pb0.55Sr1.6La0.4CuO6+δ (OP-Bi2201, Tc ≃ 34 K) are investigated by Cu L3 edge resonant inelastic x-ray scattering (RIXS), below and above the pseudogap opening temperature. At both temperatures the broad spectral distribution disperses along the (1,0) direction up to ~350 meV at zone boundary, similar to other hole-doped cuprates. However, above ~0.22 reciprocal lattice units, we observe a concurrent intensity decrease for magnetic excitations and quasielastic signals with weak temperature dependence. This anomaly seems to indicate a coupling between magnetic, lattice, and charge modes in this compound. We also compare the magnetic excitation spectra near the antinodal zone boundary in the single layer OP-Bi2201 and in the bilayer optimally doped Bi1.5Pb0.6Sr1.54CaCu2O8+δ (OP-Bi2212, Tc ≃ 96 K). Finally, the strong similarities in the paramagnon dispersion and in their energy at zone boundary indicate that the strength of the superexchange interaction and the short-range magnetic correlation cannot be directly related to Tc, not even within the same family of cuprates.