Electronic Structure of Doped Lanthanum Cuprates Studied with Resonant Inelastic X-Ray Scattering

Abstract

We report a comprehensive Cu $K$-edge RIXS investigation of $\mathrm{L}{\mathrm{a}}_{2-\mathrm{x}}\mathrm{S}{\mathrm{r}}_{\mathrm{x}}\mathrm{Cu}{\mathrm{O}}_4$ (LSCO) for 0$\le$x$\le$0.35, stripe-ordered $\mathrm{L}{\mathrm{a}}_{1.875}\mathrm{B}{\mathrm{a}}_{0.125}\mathrm{Cu}{\mathrm{O}}_4$ (LBCO), and $\mathrm{L}{\mathrm{a}}_2\mathrm{C}{\mathrm{u}}_{0.96}\mathrm{N}{\mathrm{i}}_{0.04}{\mathrm{O}}_4$ (LCNO) crystals. The RIXS spectra measured at three high-symmetry momentum transfer (\textbf{q}) positions are compared as a function of doping and for the different dopants. The spectra in the energy range 1-6 eV can be described with three broad peaks, which evolve systematically with increased doping. The most systematic trend was observed for \textbf{q}=($\pi$, 0) corresponding to the zone boundary. As hole doping increased, the spectral weight transfer from high energies to low energies is nearly linear with \emph{x} at this \textbf{q}. We interpret the peaks as interband transitions in the context of existing band models for this system, assigning them to Zhang-Rice band$\to$upper Hubbard band, lower-lying band$\to$upper Hubbard band, and lower-lying band$\to$Zhang-Rice band transitions. The spectrum of stripe-ordered LBCO was also measured, and found to be identical to the correspondingly doped LSCO, except for a relative enhancement of the near-infrared peak intensity around 1.5-1.7 eV. The temperature dependence of this near-infrared peak in LBCO was more pronounced than for other parts of the spectrum, continuously decreasing in intensity as the temperature was raised from 25 K to 300 K. Finally, we find that 4\% Ni substitution in the Cu site has a similar effect on the spectra as does Sr substitution in the La site.

10 pages (according to my pdf), 8 figures. Was accepted for publication in PRB. When I did the preview in the previous step, somehow figure 2 looked very broken into pieces ?

References in corpus (10)

• Quantum oscillations and the Fermi surface in an underdoped high-Tc superconductor
• Electron pockets in the Fermi surface of hole-doped high-Tc superconductors
• Measurement of x-ray absorption spectra of overdoped high-temperature cuprate superconductors: Inapplicability of the single-band Hubbard model
• Ultrashort Lifetime Expansion for Indirect Resonant Inelastic X-ray Scattering
• Correlation Strength, Gaps and Particle-Hole Asymmetry in High-Tc Cuprates: a Dynamical Mean Field Study of the Three-Band Copper-Oxide Model
• Magnetic nature of the 500 meV peak in $\mathrm{L}{\mathrm{a}}_{2-\mathrm{x}}\mathrm{S}{\mathrm{r}}_{\mathrm{x}}\mathrm{Cu}{\mathrm{O}}_4$ observed with resonant inelastic x-ray scattering at the Cu $K$-edge
• Charge-transfer exciton in La2CuO4 probed with resonant inelastic x-ray scattering
• Isosbestic points in the spectral function of correlated electrons
• Magnetic field dependence of charge stripe order in La2-xBaxCuO4 (x~1/8)
• Charge Excitations in Cuprate and Nickelate in Resonant Inelastic X-Ray Scattering

Cited by in corpus (6)

• Bimagnon studies in cuprates with Resonant Inelastic X-ray Scattering at the O K edge. II - The doping effect in La2-xSrxCuO4
• Evolution of plasmon excitations across the phase diagram of the cuprate superconductor La${}_{2-x}$Sr${}_x$CuO${}_4$
• Resonant inelastic X-ray scattering study of intra-band charge excitations in hole-doped high-Tc cuprates
• Neutron Scattering Studies of Spin-Phonon Hybridization and Superconducting Spin-Gaps in High Temperature Superconductor $L{a}_{2-x}(Sr,Ba{)}_{x}Cu{O}_4$
• Polarization-dependent resonant inelastic X-ray scattering study at the Cu L and O K-edge of YBa${}_2$Cu${}_3$O${}_{7-x}$
• Numerical study of resonant inelastic X-ray scattering at the oxygen $K$-edge in insulating cuprates