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arXiv · 0811.2456

Dynamics in two-leg spin ladder with a four-spin cyclic interaction

S. Nishimoto·M. Arikawa
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Abstract

We study two-leg Heisenberg ladder with four-spin cyclic interaction using the (dynamical) density-matrix renormalization group method. We demonstrate the dependence of the low-lying excitations in the spin wave, staggered dimer order, and scalar-chirality order structure factors on the four-spin cyclic interaction. We find that the cyclic interaction enhances spin-spin correlations with wave vector around momentum $(q_x,q_y)=(\fracπ{2},0)$. Also, the presence of long-range order in the staggered dimer and scalar-chirality phases is confirmed by a $δ$-function peak contribution of the structure factors at energy $ω=0$.

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S. Nishimoto, M. Arikawa. 2008-11-17. Dynamics in two-leg spin ladder with a four-spin cyclic interaction. https://doi.org/10.1103/physrevb.79.113106

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