Muon Spin Relaxation and Neutron Diffraction Studies of Cluster-Glass States in Sr1−xLaxRuO3

To clarify the magnetic properties of cluster-glass states in Sr1−xLaxRuO3 (0.3 ≤ x ≤ 0.5), we report herein the results of muon spin relaxation (μSR) and neutron powder diffraction measurements. The μSR experiments showed that magnetic clusters start developing well above the peak temperature T* in the ac susceptibility. The volume fraction of the magnetically ordered region increases continuously with decreasing temperature, showing no anomaly at T*, and reaches nearly 100% at the lowest temperature. The temperature variation of the volume fraction is essentially independent of the La concentration in the x range presently investigated, although the dc magnetization is significantly suppressed with increasing x. Neutron powder diffraction experiments revealed that the ground state for x = 0.3 is a long-range ferromagnetic ordered state. These results indicate that, with decreasing temperature, cluster-glass states in Sr1−xLaxRuO3 gradually develop into long-range ferromagnetic ordered states with decrea...