2004/04/30 by Young-June Kim, Young‐June Kim, J. P. Hill +6 · 3 citations
Earth and Planetary Sciences · Physics and Astronomy · #Advanced Condensed Matter Physics #High-pressure geophysics and materials #Physics of Superconductivity and Magnetism #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.70.094524
published as Phys. Rev. B 70, 094524 (2004) · 7 pages, 6 figures, to appear in Phys. Rev. B
arxiv created 2004/07/14 · openalex publication_date 2004/09/30 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We report a resonant inelastic x-ray scattering (RIXS) study of the doping dependence of charge-transfer excitations in La_2\ensuremath-xSrxCuO4. The momentum dependence of these charge excitations are studied over the whole Brillouin zone in underdoped (x=0.05) and optimally doped (x=0.17) samples, and compared with that of the undoped (x=0) sample. We observe a large change in the RIXS spectra between the x=0 and x=0.17 samples, while the RIXS spectra of the x=0.05 sample are similar to that of the x=0 sample. The most prominent effect of doped holes on the charge excitation spectra is the appearance of a continuum of intensity, which exhibits strong momentum dependence below 2\phantom\rule0.3em0exeV. For the x=0.17 sample, some of the spectral weight from the lowest-lying charge-transfer excitation of the undoped compound is transferred to the continuum intensity below the gap, in agreement with earlier optical studies. However, the higher-energy charge-transfer excitation carries significant spectral weight even for the x=0.17 sample. The doping dependence of the dispersion of this charge-transfer excitation is also discussed and compared with recent theoretical calculations.