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Frustration-induced eta inversion in the S=1/2 bond-alternating spin chain

Nobuya Maeshima·Kouichi Okunishi·Kiyomi Okamoto·Tôru Sakai
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Abstract

We study the frustration-induced enhancement of the incommensurate correlation for a bond-alternating quantum spin chain in a magnetic field, which is associated with a quasi-one-dimensional organic compound F5PNN. We investigate the temperature dependence of the staggered susceptibilities by using the density matrix renormalization group, and then find that the incommensurate correlation becomes dominant in a certain range of the magnetic field. We also discuss the mechanism of this enhancement on the basis of the mapping to the effective S=1/2 XXZ chain and a possibility of the field-induced incommensurate long range order.

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Nobuya Maeshima, Kouichi Okunishi, Kiyomi Okamoto, Tôru Sakai. 2004-08-07. Frustration-induced eta inversion in the S=1/2 bond-alternating spin chain. https://doi.org/10.1103/physrevlett.93.127203

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