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تسجيل مستخدم جديدTunable Giant Exchange Bias in an Intercalated Transition Metal Dichalcogenide
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The interplay of symmetry and quenched disorder leads to some of the most fundamentally interesting and technologically important properties of correlated materials. It also poses the most vexing of theoretical challenges. Nowhere is this more apparent than in the study of spin glasses. A spin glass is characterized by an ergodic landscape of states - an innumerable number of possibilities that are only weakly distinguished energetically, if at all. We show in the material Fe$_x$NbS$_2$, this landscape of states can be biased by coexisitng antiferromagnetic order. This process leads to a phenomenon of broad technological importance: giant, tunable exchange bias. We observe exchange biases that exceed those of conventional materials by more than two orders of magnitude. This work illustrates a novel route to giant exchange bias by leveraging the interplay of frustration and disorder in exotic materials.
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Recent advances in tuning the correlated behavior of graphene and transition-metal dichalcogenides (TMDs) have opened a new frontier in the study of many-body physics in two dimensions and promise exciting possibilities for new quantum technologies.
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In this paper, we have found a family of intermetallic compounds YMn12-xFex (x = 6.6-8.8) showing a bulk form of tunable giant exchange bias effect which arises from global interactions among ferromagnetic (FM) and antiferromagnetic (AFM) sublattices
but not the interfacial exchange coupling or inhomogeneous magnetic clusters. A giant exchange bias with a loop shift up to 6.1 kOe has been observed in YMn4.4Fe7.6 compound with the strongest competing magnetic interactions. In a narrow temperature range, the exchange bias field shows a sudden switching off whereas the coercivity shows a sudden switching on with increasing temperature. This unique feature indicates that the inter-sublattice exchange coupling is highly homogenous, which can be perfectly interperated by our theoretical calculations.
The exchange bias effect is an essential component of magnetic memory and spintronic devices. Whereas recent research has shown that anisotropies perpendicular to the device plane provide superior stability against thermal noise, it has proven remark
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The discovery of materials with improved functionality can be accelerated by rational material design. Heusler compounds with tunable magnetic sublattices allow to implement this concept to achieve novel magnetic properties. Here, we have designed a
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