Dynamical structure factors of $S=1/2$ two-leg spin ladder systems

Nobuyasu Haga; Sei-ichiro Suga

doi:10.1103/physrevb.66.132415

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Dynamical structure factors of $S=1/2$ two-leg spin ladder systems

Nobuyasu Haga·Sei-ichiro Suga

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Abstract

We investigate dynamical properties of $S=1/2$ two-leg spin ladder systems. In a strong coupling region, an isolated mode appears in the lowest excited states, while in a weak coupling region, an isolated mode is reduced and the lowest excited states become a lower bound of the excitation continuum. We find in the system with equal intrachain and interchain couplings that due to a cyclic four-spin interaction, the distribution of the weights for the dynamical structure factor and characteristics of the lowest excited states are strongly influenced. The dynamical properties of two systems proposed for ${\rm SrCu_2O_3}$ are also discussed.

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Nobuyasu Haga, Sei-ichiro Suga. 2002-10-31. Dynamical structure factors of $S=1/2$ two-leg spin ladder systems. https://doi.org/10.1103/physrevb.66.132415

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