Fig. 4: High transverse-field μSR data of α-Ru1−xCrxCl3 (x = 0.04).
a Normalized FFT amplitudes of hTF-μSR in applied fields of Bext//c = 0.2–3 T at T = 15 K. The data are vertically shifted for clarity. b, c Magnified views of normalized FFT amplitudes at Bext = 0.5 and 3 T. The black solid lines denote the total fitting lines that are a sum of two Lorentzian damped cosines (yellow and green lines). d, e Temperature dependence of the muon Knight shift for the fast (Kf) and slow (Ks) relaxing components in applied fields of Bext//c = 0.5 and 3 T. Kf(T) is described by power-law behaviors Kf ~ T−n (dashed lines), which deviates below TN2 = 12 K, while Ks(T) exhibits a logarithmic dependence Ks~ln(D/T) (solid lines) predicted for a singlet vortex case above 10 K. Error bars represent one standard deviation. f, g Muon spin-relaxation rates for the fast (λf) and slow (λs) component as a function of temperature on a double logarithmic scale. λf(T) displays a power-law down to TN2 (dashed lines), similar to Kf. On the other hand, λs(T) at Bext = 3 T is well described by a logarithmic dependence λs ~ 1/T1 ~ T[ln(D/T)]2 (solid lines). Error bars of the muon Knight shift and the relaxation rat represent one standard deviation of the fit parameters.
