Logarithmic dynamic scaling in spin-glasses

Evidence is presented that "freezing" in spin-glasses is a consequence of anomalous critical slowing down associated with a zero-temperature transition: temperature and field dependences of the relaxation time are compatible with lnτ∝T^-νzf(HT^-Δ) both for nearest-neighbor ±{}J-Ising models and Eu0.4{Sr}0.6$S. The exponents ${ν},z$, and ${Δ}$ are estimated. Also, the nonlinear susceptibility of $Cu$ Mu 1% is shown to be very similar to that of the $d=3$, $±{}J$ model, compatible with our description.