Three-dimensional Heisenberg spin-glass behavior in SrFe0.90Co0.10O3.0

The series SrFe1-xCoxO3 evolves from spiral antiferromagnetic order to long-range ferromagnetism on increasing Co doping. In the Fe-rich region below the onset of ferromagnetism (x <= 0.20), there exists a number of disordered magnetic ground states. Here we present a detailed study of the composition SrFe0.90Co0.10O3, which we find to display quasicanonical spin-glass behavior. The analysis of its freezing transition by means of muon spin relaxation (mu SR) spectroscopy and ac and dc susceptibility suggests that the system constitutes a new experimental realization of the three-dimensional Heisenberg spin-glass model with weak random anisotropy. The derived critical exponents are consistent with predictions by Kawamura's chiral driven freezing scenario with a bimodal exchange distribution.