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Experimental realization of a 2D fractional quantum spin liquid

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 نشر من قبل Radu Coldea
 تاريخ النشر 2000
  مجال البحث فيزياء
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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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