The unoccupied electronic structure for the Sr14Cu24O41 family of two-leg ladder compounds was investigated for different partial substitutions of Sr2+ by Ca2+, leaving the nominal hole count constant, and by Y3+ or La3+, 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 Sr14Cu24O41. On substitution of-Ca for Sr orbitals within the ladder planes but perpendicular to the legs receive some hole occupation as well.
|Number of pages||9|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - Dec 1 2000|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics