Abstract
Zero-field muon spin rotation and magnetization measurements were performed in LaCuO, for , where Cu is replaced either by or by spinless impurity. It is shown that while the doping dependence of the sublattice magnetization [] is nearly the same for both compounds, the Néel temperature [] decreases unambiguously more rapidly in the Zn-doped compound. This difference, not taken into account within a simple dilution model, is associated with the frustration induced by the Zn impurity onto the Cu antiferromagnetic lattice. In fact, from and the spin stiffness is derived and found to be reduced by Zn doping more significantly than expected within a dilution model. The effect of the structural modifications induced by doping on the exchange coupling is also discussed.
- Received 7 March 2011
DOI:https://doi.org/10.1103/PhysRevB.83.180411
©2011 American Physical Society