Evidence for spinon localization in the heat transport of the spin-1/2 ladder compound (C5H12N)(2)CuBr4

• Published in: Phys. Rev. B, vol. 80, num. 22, p. 220411
• Publication date: 2009

We present experiments on the magnetic-field-dependent thermal transport in the spin-1/2 ladder system (C5H12N)(2)CuBr4. The thermal conductivity kappa(B) is only weakly affected by the field-induced transitions between the gapless Luttinger-liquid state realized for B-c1 < B < B-c2 and the gapped states, suggesting the absence of a direct contribution of the spin excitations to the heat transport. We observe, however, that the thermal conductivity is strongly suppressed by the magnetic field deeply within the Luttinger-liquid state. These surprising observations are discussed in terms of localization of spinons within finite ladder segments and spinon-phonon umklapp scattering of the predominantly phononic heat transport.

Note: LQM

Keywords: Luttinger liquid; organic compounds; spin-phonon interactions; thermal conductivity; umklapp process

Reference

• LQM-ARTICLE-2010-001
• doi:10.1103/PhysRevB.80.220411
• View record in Web of Science

Record created on 2010-02-08, modified on 2012-03-21