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Scaling of dynamic spin correlations in BaCu2SiGeO7

A. Zheludev·T. Masuda·G. Dhalenne·A. Revcolevschi·C. Frost·T. Perring
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Abstract

The magnetic dynamic structure factor of the one-dimensional S = 1/2 chain system BaCu2(Si0.5Ge0.5)2O7 is studied in a wide range of energy transfers and temperatures. Contrary to previous erroneous reports [T. Masuda et al., Phys. Rev. Lett. 93, 077206 (2004)], the scaling properties observed in the range 0.5-25 meV are found to be fully consistent with expectations for a Luttinger spin liquid. At higher energies, a breakdown of scaling laws is observed and attributed to lattice effects. The results are complementary to those found in literature for other S = 1/2-chain compounds, such as KCuF3 and Cu-benzoate.

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A. Zheludev, T. Masuda, G. Dhalenne, A. Revcolevschi, C. Frost, T. Perring. 2006-11-01. Scaling of dynamic spin correlations in BaCu2SiGeO7. https://doi.org/10.1103/physrevb.75.054409

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