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arXiv · cond-mat/0501243

Wigner crystallization in Na(3)Cu(2)O(4) and Na(8)Cu(5)O(10) chain compounds

Abstract

We report the synthesis of novel edge-sharing chain systems Na(3)Cu(2)O(4) and Na(8)Cu(5)O(10), which form insulating states with commensurate charge order. We identify these systems as one-dimensional Wigner lattices, where the charge order is determined by long-range Coulomb interaction and the number of holes in the d-shell of Cu. Our interpretation is supported by X-ray structure data as well as by an analysis of magnetic susceptibility and specific heat data. Remarkably, due to large second neighbor Cu-Cu hopping, these systems allow for a distinction between the (classical) Wigner lattice and the 4k_F charge-density wave of quantum mechanical origin.

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P. Horsch, M. Sofin, M. Mayr, M. Jansen. 2005-01-11. Wigner crystallization in Na(3)Cu(2)O(4) and Na(8)Cu(5)O(10) chain compounds. https://doi.org/10.1103/physrevlett.94.076403

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