dc magnetic field, this nanomanganite exhibits that the exchange bias effect. As a consequence, the magnetization reversal mechanism of the system is changed from an AFM/FiM rigid-coupling regime to an exchange-biased regime, providing a new approach to tune the magnetic properties and to design novel hybrid nanostructures. Unravelling the onset of the exchange bias effect in Ni (core) NiO (shell) nanoparticles embedded in a mesoporous carbon matrix. Temperature-dependent magnetization of core-shell particles at high fields shows a deviation between field-cooled and zero-field-cooled curves below 30 K, suggesting the presence of frozen spins at the interface. fact that there exists a coupling between the SG shell and the AFM core in. We found that the relationship between the AFM anisotropy energy and the exchange coupling energy can be tuned by replacing Co 2+ with Zn 2+ ions in the shell. The exchange coupling across the interface between a ferromagnetic core and an antiferromagnetic shell or vice versa causes this effect. While H C decreases monotonically with the Zn concentration from ∼21.5 kOe for x = 0, to ∼7.1 kOe for x = 1, H EB exhibits a non-monotonous behavior being maximum, H EB ∼ 1.4 kOe, for intermediate concentrations. In case of nanoparticles, the exchange bias (EB) effect could be established by a system which contains two kinds of exchange coupled spins such as frozen spins that cannot be reversed and the other rotatable spins that can be reversed by applying field 11. The exchange bias (EB) is an effect occurring in coupled ferromagnetic/antiferromagnetic materials of diverse shapes, from coreshell nanoparticles to. The system presents an enhancement of the coercivity ( H C) as compared to its FiM single-phase counterpart and exchange bias fields ( H EB). The nanoparticles are constituted by a ∼3 nm antiferromagnetic (AFM) CoO core encapsulated in a ∼4 nm-thick Co 1− xZn xFe 2O 4 ( x = 0–1) ferrimagnetic (FiM) shell. The exchange coupling at the interface of nanosized coreshell nanoparticles, comprised of ferromagnetic metallic cores and antiferromagnetic oxide-metal shells. In order to explore an alternative strategy to design exchange-biased magnetic nanostructures, bimagnetic core/shell nanoparticles have been fabricated by a thermal decomposition method and systematically studied as a function of the interface exchange coupling.
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