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Doped coupled frustrated spin-1/2 chains with four-spin exchange

Nicolas Laflorencie·Didier Poilblanc
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Abstract

The role of various magnetic inter-chain couplings is investigated by numerical methods in doped frustrated quantum spin chains. A non-magnetic dopant introduced in a gapped spin chain releases a free spin-1/2 soliton. The formation of a local magnetic moment is analyzed in term of soliton confinement. A four-spin coupling which might originate from cyclic exchange is shown to produce such a confinement in contrast to transverse magnetic exchange. Dopants on different chains experience an effective space-extended non-frustrating pairwise spin interaction.

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Nicolas Laflorencie, Didier Poilblanc. 2003-04-17. Doped coupled frustrated spin-1/2 chains with four-spin exchange. https://doi.org/10.1103/physrevlett.90.157202

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