The fine structures of the oxygen K-edge in Tl2Ba2Can-1CunO2n+4 (n=1-3) with double Tl-O layers were investigated by electron energy loss spectroscopy (EELS). A peak at 528 eV becomes smaller with the increase of the number of Cu-O layers, n, in Tl2Ba2Can-1CunO2n+4, indicating that the average hole content in a Cu-O bonding decreases with the increase of n. Reducing the hole content in Tl2Ba2Cu1O6 by replacing a part of Ba(+2) with La(+3), the peak at 528 eV becomes smaller and Tc of the compounds increases up to 55 K. It was shown that holes of Tl2Ba2Cu1O6 are overdoped. The present EELS results were compared with the previous results of Tl1Ba2Can-1CunO2n+3 with single Tl-O layers.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering