μSR study of the Cu-spin dynamics in La2−xSrxCu1−yZnyO4 Original Research Article

In order to clarify the effect of non-magnetic impurities on the dynamics of the Cu spin, muon-spin relaxation measurements have been carried out on the Zn-substituted La2−xSrxCu1−yZnyO4 with x=0.13, changing the Zn concentration (0≤y≤0.10). Although the Cu spins at y=0 have been confirmed to be in the paramagnetic state down to at least 2 K, clear muon-spin precession has been observed at the same temperature at y=0.01. This muon-spin precession has disappeared at y≥0.05 and the muon-spin depolarization at low temperatures has become small with increasing y at y>0.01, indicating that the magnetic correlation between Cu spins becomes weaker as the value of y increases at y>0.01. The present result proves that a small amount of non-magnetic impurities operate to statically stabilize the dynamical stripe correlations of spins and holes but a large quantity of non-magnetic impurities destroy the stripe correlations themselves.