Resonant X-ray scattering measurements of a spatial modulation of the Cu 3d and O 2p energies in stripe-ordered cuprate superconductors

Phys Rev Lett. 2013 Jan 4;110(1):017001. doi: 10.1103/PhysRevLett.110.017001. Epub 2013 Jan 2.

Abstract

A prevailing description of the stripe phase in underdoped cuprate superconductors is that the charge carriers (holes) phase segregate on a microscopic scale into hole-rich and hole-poor regions. We report resonant elastic x-ray scattering measurements of stripe-ordered La(1.475)Nd(0.4)Sr(0.125)CuO(4) at the Cu L and O K absorption edges that identify an additional feature of stripe order. Analysis of the energy dependence of the scattering intensity reveals that the dominant signature of the stripe order is a spatial modulation in the energies of Cu 3d and O 2p states rather than the large modulation of the charge density (valence) envisioned in the common stripe paradigm. These energy shifts are interpreted as a spatial modulation of the electronic structure and may point to a valence-bond-solid interpretation of the stripe phase.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Copper / chemistry*
  • Electric Conductivity
  • Electrons*
  • Models, Chemical*
  • Oxygen / chemistry*
  • X-Ray Absorption Spectroscopy / methods
  • X-Ray Diffraction / methods*

Substances

  • Copper
  • Oxygen