Raman and fluorescence characteristics of resonant inelastic X-ray scattering from doped superconducting cuprates

• DOI: 10.1038/srep19657
• Publication Date: 2016-01-22T10:10:20Z
• Authors: H. Y. Huang; C. J. Jia; Z. Y. Chen; K. Wohlfeld; B. Moritz; T. P. Devereaux; W. B. Wu; J. Okamoto; W. S. Lee; M. Hashimoto; Y. He; Z. X. Shen; Y. Yoshida; H. Eisaki; C. Y. Mou; C. T. Chen; D. J. Huang
• Keywords: Superconductivity (cond-mat.supr-con); Condensed Matter - Superconductivity; 0103 physical sciences; FOS: Physical sciences; 01 natural sciences; Article

Measurements of spin excitations are essential for an understanding spin-mediated pairing superconductivity; and resonant inelastic X-ray scattering (RIXS) provides a considerable opportunity to probe high-energy excitations. However, whether RIXS correctly measures the collective doped superconducting cuprates remains under debate. Here we demonstrate distinct Raman- fluorescence-like Bi$_{1.5}$Pb$_{0.6}$Sr$_{1.54}$CaCu$_{2}$O$_{8+{\delta}}$ in mid-infrared energy region. Combining photon-energy momentum dependent measurements with theoretical calculations using exact diagonalization conclusive evidence that Raman-like correspond excitations, which magnons undoped Mott insulators evolve into paramagnons compounds. In contrast, shifts due primarily continuum particle-hole charge channel. Our results show proper experimental conditions indeed can be used high-$T_c$ cuprate superconductors.