Abstract
We have studied the thermal conductivity on single crystalline samples of the antiferromagnetic monolayer cuprates with , Pr, Nd, Sm, Eu, and Gd. For a heat current within the planes, i.e., for we find high-temperature anomalies around in all samples. In contrast, the thermal conductivity perpendicular to the planes, which we measured for , Pr, and Gd, shows a conventional temperature dependence as expected for a purely phononic thermal conductivity. This qualitative anisotropy of and the anomalous temperature dependence of give evidence for a significant magnetic contribution to the heat transport within the planes. Our results suggest, that a large magnetic contribution to the heat current is a common feature of single-layer cuprates. We find that is hardly affected by structural instabilities, whereas already weak charge carrier doping causes a strong suppression of .
- Received 15 September 2005
DOI:https://doi.org/10.1103/PhysRevB.73.104430
©2006 American Physical Society