Critical spin-glass dynamics in a heterogeneous nanogranular system
نویسندگان
چکیده
The analysis of ac magnetic susceptibility data has shown that mechanically alloyed Fe30Ag40W30 , a highly heterogeneous nanogranular system, exhibits critical dynamics in its transition to a low-temperature spin-glasslike phase, as proved by the power-law divergence of the relaxation time at Tg519.7 K, and by the dynamic scaling behavior of the out-of-phase component of the susceptibility. Both analyses yielded a dynamic critical exponent zn510.260.9, confirming the existence of a spin-glass-like phase transition at Tg , which, however, is not accompanied by the usual Mössbauer signature.
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