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arXiv · 0807.1571

Dimensional crossover in a spin liquid to helimagnet quantum phase transition

V. O. Garlea·A. Zheludev·K. Habicht·M. Meissner·B. Grenier·L. -P. Regnault·E. Ressouche
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Abstract

Neutron scattering is used to study magnetic field induced ordering in the quasi-1D quantum spin-tube compound Sul--Cu$_2$Cl$_4$ that in zero field has a non-magnetic spin-liquid ground state. The experiments reveal an incommensurate chiral high-field phase stabilized by a geometric frustration of the magnetic interactions. The measured critical exponents $β\approx0.235$ and $ν\approx0.34$ at $H_c\approx3.7$ T point to an unusual sub-critical scaling regime and may reflect the chiral nature of the quantum critical point.

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V. O. Garlea, A. Zheludev, K. Habicht, M. Meissner, B. Grenier, L. -P. Regnault, E. Ressouche. 2009-02-03. Dimensional crossover in a spin liquid to helimagnet quantum phase transition. https://doi.org/10.1103/physrevb.79.060404

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