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arXiv · 0807.2896

Quantized Berry Phases of a Spin-1/2 Frustrated Two-Leg Ladder with Four-Spin Exchange

I. Maruyama·T. Hirano·Y. Hatsugai
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Abstract

A spin-1/2 frustrated two-leg ladder with four-spin exchange interaction is studied by quantized Berry phases. We found that the Berry phase successfully characterizes the Haldane phase in addition to the rung-singlet phase, and the dominant vector-chirality phase. The Hamiltonian of the Haldane phase is topologically identical to the S=1 antiferromagnetic Heisenberg chain. Decoupled models connected to the dominant vector-chirality phase revealed that the local object identified by the non-trivial ($\pi$) Berry phase is the direct product of two diagonal singlets.

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I. Maruyama, T. Hirano, Y. Hatsugai. 2008-07-18. Quantized Berry Phases of a Spin-1/2 Frustrated Two-Leg Ladder with Four-Spin Exchange. https://doi.org/10.1088/1742-6596/145/1/012052

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