MAGNETIC-ORDERING AND FLUCTUATIONS IN THE S = 1/2 SQUARE HEISENBERG-ANTIFERROMAGNET CU(DCO2)2.4D2O

Journal article

Elastic and quasielastic neutron scattering measurements have been performed in the S=1/2 square Heisenberg antiferromagnet copper(II) deuteroformate tetradeuterate, Cu(DCO2)2.4D2O. The sublattice magnetization was measured below TN=16.54(5) K, and the critical exponent beta was found to cross over from 0.23(1) to 0.32(2) at a reduced temperature epsilon =(TN-T)/TN of 0.06 as T N was approached from below. The temperature dependence of the inverse correlation length of the two-dimensional antiferromagnetic correlations and of the sublattice susceptibility above TN was consistent with the predictions of the quantum non-linear sigma model of Chakravarty (1989) and co-workers for a spin-wave stiffness of 13.4(4) K.

Authors: Clarke, S; Harrison, A; Mason, T; Mcintyre, G; Visser, D

• Publication status: Published
• Journal: JOURNAL OF PHYSICS-CONDENSED MATTER
• Volume: 4
• Issue: 4
• Pages: L71-L76
• Publication date: 1992-01-27
• DOI: 10.1088/0953-8984/4/4/003
• EISSN: 1361-648X
• ISSN: 0953-8984
• Language: English