Sm. Stinnett et al., The relationship between the dynamic remanent coercivity and the viscosityand irreversible susceptibility in magnetic media, IEEE MAGNET, 36(1), 2000, pp. 148-153
It has been established previously that thermal switching in high density m
agnetic media causes a significant time dependence of the coercivity at lea
st for times > 10(-8) s, Here, the classical Arrhenius-Neel model assuming
coherent rotation is applied to systems with distributions in volume, aniso
tropy and orientation and the numerical results for the time dependent rema
nent coercivity H-CR(t), the viscosity SR, and the irreversible susceptibil
ity, chi(IRR) compared to new experimental data on CrO2 particulate tapes w
ith varying orientation. The results for an anisotropy distribution are sig
nificantly different from a volume distribution and are in better agreement
with the data. All distributions produce Sharrock type behavior for H-CR(t
), regardless of the distribution width. The model predicts that increasing
the orientation distribution width will have very little effect on the fra
ctional time dependence of N-CR, in agreement with experiment which showed
that S-R/chi(IRR) and HCR(t) were essentially independent of orientation. F
inally, the direct connection between S-R/chi(IRR) and N-CR(t) is confirmed
theoretically and experimentally.