1. Hole distribution for (Sr,Ca,Y,La)_14 Cu_24 O_41 ladder compounds studied by x-ray absorption spectroscopy
- Author
-
Nücker, N., Merz, M., Kuntscher, C. A., Gerhold, S., Schuppler, S., Neudert, R., Golden, M. S., Fink, J., Schild, D., Stadler, S., Chakarian, V., Freeland, J., Idzerda, Y. U., Conder, K., Uehara, M., Nagata, T., Goto, J., Akimitsu, J., Motoyama, N., Eisaki, H., Uchida, S., Ammerahl, U., and Revcolevschi, A.
- Subjects
Condensed Matter - Strongly Correlated Electrons ,Condensed Matter - Superconductivity - Abstract
The unoccupied electronic structure for the Sr_14Cu_24O_41 family of two-leg ladder compounds was investigated for different partial substitutions of Sr^2+ by Ca^2+, leaving the nominal hole count constant, and by Y^3+ or La^3+, reducing the nominal hole count from its full value of 6 per formula unit. Using polarization-dependent x-ray absorption spectroscopy on single crystals, hole states on both the chain and ladder sites could be studied. While for intermediate hole counts all holes reside on O sites of the chains, a partial hole occupation on the ladder sites in orbitals oriented along the legs is observed for the fully doped compound Sr_14Cu_24O_41. On substitution of Ca for Sr orbitals within the ladder planes but perpendicular to the legs receive some hole occupation as well., Comment: 10 pages RevTeX style with 7 embedded figures + 1 table; accepted by Phys. Rev. B
- Published
- 2000
- Full Text
- View/download PDF