| DOI | Resolve DOI: https://doi.org/10.1103/PhysRevB.66.024407 |
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| Author | Search for: Kenzelmann, M.; Search for: Cowley, R. A.; Search for: Buyers, W. J. L.1; Search for: Tun, Z.1; Search for: Coldea, R.; Search for: Enderle, M. |
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| Affiliation | - National Research Council Canada. NRC Canadian Neutron Beam Centre
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| Format | Text, Article |
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| Abstract | We report inelastic time-of-flight and triple-axis neutron scattering measurements of the excitation spectrum of the coupled antiferromagnetic spin-1 Heisenberg chain system CsNiCl3. Measurements over a wide range of wave-vector transfers along the chain confirm that above TNCsNiCl3 is in a quantum-disordered phase with an energy gap in the excitation spectrum. The spin correlations fall off exponentially with increasing distance with a correlation length ξ=4.0(2) sites at T=6.2K. This is shorter than the correlation length for an antiferromagnetic spin-1 Heisenberg chain at this temperature, suggesting that the correlations perpendicular to the chain direction and associated with the interchain coupling lower the single-chain correlation length. A multiparticle continuum is observed in the quantum-disordered phase in the region in reciprocal space where antiferromagnetic fluctuations are strongest, extending in energy up to twice the maximum of the dispersion of the well-defined triplet excitations. We show that the continuum satisfies the Hohenberg-Brinkman sum rule. The dependence of the multiparticle continuum on the chain wave vector resembles that of the two-spinon continuum in antiferromagnetic spin-1/2 Heisenberg chains. This suggests the presence of spin-1/2 degrees of freedom in
CsNiCl3 for T<~12K, possibly caused by multiply frustrated interchain interactions. |
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| Publication date | 2002-06-28 |
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| In | |
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| Language | English |
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| NPARC number | 12338093 |
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| Export citation | Export as RIS |
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| Report a correction | Report a correction (opens in a new tab) |
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| Record identifier | 198f308d-0d08-4977-a6b8-5fcb5beb83da |
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| Record created | 2009-09-10 |
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| Record modified | 2020-04-06 |
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