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arXiv:cond-mat/0302452 · Physical review. B, Condensed matter

Statistics of spinons in the spin-liquid phase of Cs2CuCl4

Chung‐Hou Chung, Klaus Voelker, Yong Baek Kim

Published Sep 12, 2003• 39 citations
arXivHTMLPDF

Abstract

Motivated by a recent experiment on ${\mathrm{Cs}}_{2}{\mathrm{CuCl}}_{4}$ [Coldea et al., Phys. Rev. Lett. 86, 1335 (2001)], we study the spin dynamics of the spin-liquid phase of the $\mathrm{s}\mathrm{p}\mathrm{i}\mathrm{n}\ensuremath{-}\frac{1}{2}$ frustrated Heisenberg antiferromagnet on the anisotropic triangular lattice. There have been two different proposals for the spin-liquid phase of ${\mathrm{Cs}}_{2}{\mathrm{CuCl}}_{4}.$ These spin-liquid states support different statistics of spinons; the bosonic $\mathrm{Sp}(N)$ large-N mean-field theory predicts bosonic spinons, while the SU(2) slave-boson mean-field theory leads to fermionic spinons. We compute the dynamical spin structure factor for both types of spin-liquid state at zero and finite temperatures. While at zero temperature both theories agree with experiment on a qualitative level, they show substantial differences in the temperature dependence of the dynamical spin structure factor.

DOI
10.1103/physrevb.68.094412

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