Zero-field muon spin rotation and magnetization measurements were performed in La2Cu1-xMxO4, for 0⩽x⩽0.12, where Cu2+ is replaced either by M=Zn2+ or by M=Mg2+ spinless impurity. It is shown that while the doping dependence of the sublattice magnetization [M(x)] is nearly the same for both compounds, the Néel temperature [TN(x)] 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 Zn2+ impurity onto the Cu2+ antiferromagnetic lattice. In fact, from TN(x) and M(x) 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.
Carretta, P., Prando, G., Sanna, S., De Renzi, R., Decorse, C., Berthet, P. (2011). Evidence for impurity-induced frustration in La2CuO4. PHYSICAL REVIEW. B, CONDENSED MATTER AND MATERIALS PHYSICS, 83, 1-4 [10.1103/PhysRevB.83.180411].
Evidence for impurity-induced frustration in La2CuO4
SANNA, SAMUELE;
2011
Abstract
Zero-field muon spin rotation and magnetization measurements were performed in La2Cu1-xMxO4, for 0⩽x⩽0.12, where Cu2+ is replaced either by M=Zn2+ or by M=Mg2+ spinless impurity. It is shown that while the doping dependence of the sublattice magnetization [M(x)] is nearly the same for both compounds, the Néel temperature [TN(x)] 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 Zn2+ impurity onto the Cu2+ antiferromagnetic lattice. In fact, from TN(x) and M(x) 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.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
