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arXiv · 1406.6876

Scaling of temporal correlations in an attractive Tomonaga-Luttinger spin liquid

K. Yu. Povarov·D. Schmidiger·N. Reynolds·R. Bewley·A. Zheludev
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Abstract

We report temperature-dependent neutron scattering measurements of the local dynamic structure factor in the quantum spin ladder (C$_{7}$H$_{10}$N)$_{2}$CuBr$_{4}$ in a magnetic field $H=9$~T, in its gapless quantum-critical phase. We show that the measured quantity has a scaling form consistent with expectations for a Tomonaga-Luttinger liquid with attraction. The measured Luttinger parameter $K\approx1.25$ and scaling function are in excellent agreement with density matrix renormalization group numerical calculations for the underlying spin Hamiltonian.

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K. Yu. Povarov, D. Schmidiger, N. Reynolds, R. Bewley, A. Zheludev. 2014-06-26. Scaling of temporal correlations in an attractive Tomonaga-Luttinger spin liquid. https://doi.org/10.1103/physrevb.91.020406

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