Neutron Scattering Experiments on the Haldane Conjecture
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چکیده
Polarized neutron study of the spin dynamics for a Heisenberg antiferromagnet with easy-axis anisotropy, CsNiCl3, clearly demonstrates the almost isotropic character of the system. The study also revealed a difference between the observed and the calculated spin wave dispersion using the classical spin wave theory for T << 4.8 K and T > 4.8 K. This may be interpreted as a quantum effect on the spin dynamics in one and three dimension, as has been suggested by Haldane for one dimension.
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تاریخ انتشار 2016