MAGNETIC-ORDERING AND FLUCTUATIONS IN THE S = 1/2 SQUARE HEISENBERG-ANTIFERROMAGNET CU(DCO2)2.4D2O
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...
| Main Authors: | , , , , |
|---|---|
| Format: | Journal article |
| Language: | English |
| Published: |
1992
|
| Summary: | 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. |
|---|