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The Quasi-1D S=1/2 Antiferromagnet Cs2CuCl4 in a Magnetic Field

R. Coldea·D. A. Tennant·R. A. Cowley·D. F. McMorrow·B. Dorner·Z. Tylczynski
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Abstract

Magnetic excitations of the quasi-1D S=1/2 Heisenberg antiferromagnet (HAF) Cs2CuCl4 have been measured as a function of magnetic field using neutron scattering. For T<0.62 K and B=0 T the weak inter-chain coupling produces 3D incommensurate ordering. Fields greater than Bc =1.66 T, but less than the field (~8 T) required to fully align the spins, are observed to decouple the chains, and the system enters a disordered intermediate-field phase (IFP). The IFP excitations are in agreement with the predictions of Muller et al. for the 1D S=1/2 HAF, and Talstra and Haldane for the related 1/r^2 chain (the Haldane-Shastry model). This behaviour is inconsistent with linear spin-wave theory.

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R. Coldea, D. A. Tennant, R. A. Cowley, D. F. McMorrow, B. Dorner, Z. Tylczynski. 1997-05-22. The Quasi-1D S=1/2 Antiferromagnet Cs2CuCl4 in a Magnetic Field. https://doi.org/10.1103/physrevlett.79.151

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