Fluctuations and Correlations in SrTiO3forT>~Tc

Abstract
The linewidth broadening of the paramagnetic resonance of the Fe3+VO center in SrTiO3 near Tc has been measured accurately and analyzed for TTc+. It is found that the order-parameter susceptibility χ(q,T) is two-dimensionally anisotropic with an anisotropy parameter Δ=160. The critical exponent of the correlation length ξ is found to be ν=0.63±0.07. The EPR linewidth is cusp shaped for TTc+ and finite at T=Tc.