μSR studies of Li-doped La2CuO4

Magnetic properties of the Li-doped cuprates La2Cu1-xLixO4 (where x = 0.01, 0.05, 0.10, 0.45, and 0.50) have been studied by μSR. For low Li concentrations (x ≤ 0.10) we find a rapid suppression of TN as x increases, but little change in the magnitude and temperature dependence of the AFM order parameter. This indicates that Li doping effectively destroys AFM (similar to Sr doping, but different from Zn doping) without strongly affecting the onsite Cu moments and the shape of the spinwave excitation spectrum. For high Li concentrations we find magnetic clusters in about 15% of the sample volume; the remaining volume is non-magnetic, suggesting possible singlet-state formation.