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arXiv · 1004.4276

The Realization of Artificial Kondo Lattices in Nanostructured Arrays

D. K. Singh·M. T. Tuominen
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Abstract

The interplay of magnetic energies in a Kondo lattice is the underlying physics of a heavy fermion system. Creating an artificial Kondo lattice system by localizing the moments in an ordered metallic array provides a prototype system to tune and study the energetic interplay while avoiding the complications introduced by random alloying of the material. In this article, we create a Kondo lattice system by fabricating a hexagonally ordered nanostructured array using niobium as the host metal and cobalt as the magnetic constituent. Electrical transport measurements and magnetoresistivity measurements of these artificial lattices show that the competing exchange coupling properties can be easily tuned by controlling the impurity percentage. These artificial Kondo lattice systems enable the exploration of an artificial superconductor which should lead to a deep understanding of the role of magnetism in unconventional superconductors.

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D. K. Singh, M. T. Tuominen. 2010-04-24. The Realization of Artificial Kondo Lattices in Nanostructured Arrays. https://doi.org/10.1103/physrevb.83.014408

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