The transport properties of double doped samples La1.85-xSr0.15+xCu1-xCoxO y, (0≤x≤1.0) are investigated by means of resistivity and thermoelectric power (TEP). It is found that with Co doping, the lattice parameter a increases first and then decreases as x≥0.6, where the resistivity and thermoelectric power exhibit a corresponding anomaly. Analyzing the discrepancy of the thermal activation energy derived from the resistivity and TEP, we find that the transport mechanism can be understood in terms of the polaron model. The corresponding Ga doped system is also analyzed as a comparison. Another interesting phenomenon is the different change of the broad peaks in S-T curves between Co and Ga doped systems, which is discussed according to the change of spin correlation.
|Original language||English (US)|
|Number of pages||5|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|State||Published - May 1 1999|
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics