Interaction effects and energy barrier distribution on the magnetic relaxation of nanocrystalline hexagonal ferrites
نویسنده
چکیده
The static and dynamic magnetic properties of nanocrystalline BaFe10.4Co0.8Ti0.8O19 M -type doped barium ferrite were studied in detail to clarify the effect of interactions on the magnetic relaxation of an assembly of small particles. The logarithmic approximation was unable to account for the magnetic relaxation of the sample. Interaction effects were analyzed from the low-field susceptibility, DM plots and the time dependence of thermoremanence, indicating that demagnetizing interactions led to an enhancement of both the relaxation rate at low temperatures and the amount of the lowest energy barriers. It is thus suggested that care should be taken when analyzing thermoremanent data at low temperature, in order not to confuse these experimental findings with the signature of macroscopic quantum tunneling. @S0163-1829~97!04709-7#
منابع مشابه
The effect of magnetic interaction in barium hexaferrite particles
The effect of interactions on the magnetic relaxation of nanocrystalline hexagonal barium hexaferrite BaFe10.4Co0.8Ti0.8O19 is discussed. We had previously shown that according to the T ln(t/t0) scaling, an enhancement of the lowest-energy barriers was detected when demagnetizing interactions were dominant. Also, the Henkel plots obtained for particles of about 10 nm of mean diameter showed tha...
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