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arXiv · 0711.4094

Quasi-universal finite-$T$ scaling in gapped one-dimensional quantum magnets

A. Zheludev·V. O. Garlea·L. -P. Regnault·H. Manaka·A. Tsvelik·J. -H. Chung
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Abstract

Temperature dependencies of gap energies and magnon lifetimes are measured in the quasi-1-dimensional S=1/2 gapped quantum magnets IPA-CuCl3 and Sul-Cu2Cl4 using inelastic neutron scattering. The results are compared to those found in literature for S=1 Haldane spin chain materials and to theoretical calculations for the O(3)- and O(N)- quantum non-linear sigma-models. It is found that when the T=0 energy gap Delta is used as the temperature scale, all experimental and theoretical curves are identical to within system-dependent but temperature-independent scaling factors of the order of unity. This quasi-universality extends over a surprising broad T range, at least up to kappa T ~ 1.5 Delta.

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A. Zheludev, V. O. Garlea, L. -P. Regnault, H. Manaka, A. Tsvelik, J. -H. Chung. 2008-03-14. Quasi-universal finite-$T$ scaling in gapped one-dimensional quantum magnets. https://arxiv.org/abs/0711.4094

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