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Experimental realization of a 2D fractional quantum spin liquid

R. Coldea·D. A. Tennant·A. M. Tsvelik·Z. Tylczynski
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Abstract

The ground-state ordering and dynamics of the two-dimensional (2D) S=1/2 frustrated Heisenberg antiferromagnet Cs_2CuCl_4 is explored using neutron scattering in high magnetic fields. We find that the dynamic correlations show a highly dispersive continuum of excited states, characteristic of the RVB state, arising from pairs of S=1/2 spinons. Quantum renormalization factors for the excitation energies (1.65) and incommensuration (0.56) are large.

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R. Coldea, D. A. Tennant, A. M. Tsvelik, Z. Tylczynski. 2001-01-04. Experimental realization of a 2D fractional quantum spin liquid. https://doi.org/10.1103/physrevlett.86.1335

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