Zooming-in on the charge ordering in YBa2Cu3O6.5

D. L. Feng; A. Rusydi; P. Abbamonte; L. Venema; I. Elfimov; R. Liang; D. A. Bonn; W. N. Hardy; C. Schusler-Langeheine; S. Hulbert; C. -C. Kao; G. A. Sawatzky

paper

Zooming-in on the charge ordering in YBa2Cu3O6.5

arXiv:cond-mat/0402488

Abstract

We report direct evidence of charge/orbital ordering of low energy electronic states of $C u$ in YBa $_{2}$ Cu $_{3}$ O $_{6 + x}$ ortho-II phase in both the $C u O_{3}$ chain and the CuO $_{2}$ plane. Huge enhancement of the $(1/2, 0, 0)$ superstructure Bragg peak is observed when photon energy is tuned to the $C u L_{2, 3}$ absorption edge with large polarization dependence. The ordering in the $C u O_{2}$ plane discovered here sheds new light on how the one dimensional $C u - O$ chains affect the $C u O_{2}$ plane, and why many normal and superconducting state properties of this system exhibit strong anisotropy.

4 pages, 3 figures