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تسجيل مستخدم جديدExchange bias and asymmetric hysteresis loops from a microscopic model of core/shell nanoparticles
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We present Monte Carlo simulations of hysteresis loops of a model of a magnetic nanoparticle with a ferromagnetic core and an antiferromegnetic shell with varying values of the core/shell interface exchange coupling which aim to clarify the microscopic origin of exchange bias observed experimentally. We have found loops shifts in the field direction as well as displacements along the magnetization axis that increase in magnitude when increasing the interfacial exchange coupling. Ovelap functions computed from the spin configurations along the loops have been computed to explain the origin and magnitude of these features microscopically.
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We present an atomistic model of a single nanoparticle with core/shell structure that takes into account its lattice strucutre and spherical geometry, and in which the values of microscopic parameters such as anisotropy and exchange constants can be
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