Fig. 6: Correlated spin glass state observed by LE-μSR, SQUID, and switching dynamics.

a Temperature-dependent average local field B (top), muon damping rate λ (middle), volume fraction of the paramagnetic regions (bottom), obtained from fits of the LE-μSR data. Error bars show statistical errors as obtained from the Musrfit program. b Temperature dependent comparison of the μSR local mean field, bulk magnetization M measured by SQUID magnetometry, and XMCD switching statistics for ZFC (green markers) and FH-FC (red markers). The pictographs illustrate a muon stopping in FiM clusters embedded in a PM sea. As the clusters grow in size at lower temperatures, the average internal B-field shows a negative shift indicated by the arrow in (a). The FiM switching statistical error margins are binomial confidence intervals (obtaining x-switches in n trials gives a \(\sqrt{(x/n*(1-x/n)/n)}\) error). The statistically most relevant FiM switching, summarized from three independent beamtimes from fresh samples, was measured at 5 K (ZFC), that is why the smallest error bar in FiM switching probability is achieved under these measurement conditions.