Volume 91, Number 1, July 2010
|Number of page(s)||5|
|Section||Condensed Matter: Electronic Structure, Electrical, Magnetic and Optical Properties|
|Published online||16 July 2010|
The spin-entropy enhancement induced by Ce doping in Ca3Co4O9+δ
National Laboratory of Solid State Microstructures and Physics Department of Nanjing University Nanjing 210093, China
2 College of Physics and Technology, Guangxi Normal University - Guilin 541004, China
3 College of Science, Zhongyuan University of Technology - Zhengzhou 450007, China
Accepted: 16 June 2010
We present measurements of the thermopower as a function of temperature under different magnetic fields, for Ce-doped Ca3Co4O9+δ. A strong magnetic-field suppression of the thermopower indicates a large spin-entropy contribution. The magnetothermopower is enhanced in all doped samples, which provides an experimental evidence for the enhanced spin entropy by Ce doping. Our magnetic results allow us to determine the decrease in Co4+ concentration which results in the spin-entropy enhancement. We adopt a suitable theoretical model to explain our experimental observations. This investigation gives strong evidence that the enhanced thermopower mainly originates from enhancement of the spin entropy.
PACS: 72.20.Pa – Thermoelectric and thermomagnetic effects / 72.80.Ga – Transition-metal compounds
© EPLA, 2010
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.