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Spin-chirality duality in a spin ladder with four-spin cyclic exchange

Toshiya Hikihara·Tsutomu Momoi·Xiao Hu
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Abstract

Effect of four-spin cyclic exchange on magnetism is studied in the two-leg S=1/2 ladder. We develop an exact spin-chirality duality transformation, under which the system is self-dual when the four-spin exchange J_4 is half of the two-spin exchange. Using the density-matrix renormalization-group method and the duality relation, we find that the four-spin exchange makes the vector chirality correlation dominant. A "chirality short-range resonating-valence-bond" phase is identified for the first time at large J_4.

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Toshiya Hikihara, Tsutomu Momoi, Xiao Hu. 2003-01-28. Spin-chirality duality in a spin ladder with four-spin cyclic exchange. https://doi.org/10.1103/physrevlett.90.087204

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