Magnetic relaxation phenomena in the superspin-glass system [Co80Fe20/Al2O3]10
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چکیده
Relaxation and temperature cycles of thermoremanent magnetization, MTRM, in the superspin-glass phase of [Co80Fe20(0.9 nm)/Al2O3(3 nm)]10 have been investigated. The relaxation of MTRM exhibits ageing phenomena. In negative temperature cycles for temperature steps larger than 1 K the magnetic state is retrieved (memory effect) on returning to the measurement temperature. This property is independent of the application of a fi eld step during intermediate cooling. In positive temperature cycles the relaxation is suppressed after temporary heating. The observations are discussed in the light of both the droplet and the hierarchical picture.
منابع مشابه
Superspin glass behaviour of interacting ferromagnetic nanoparticles in discontinuous magnetic multilayers
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تاریخ انتشار 2017