MNR in antiferromagnetic Mn19F2
- 1 January 1959
- journal article
- Published by EDP Sciences in Journal de Physique et le Radium
- Vol. 20 (2-3) , 341-343
- https://doi.org/10.1051/jphysrad:01959002002-3034100
Abstract
Precise measurements have been made of the NMR frequency for 19F nuclei in antiferromagnetic MnF2. The interaction energy of 19F is assumed proportional to the mean local spin polarization of the paramagnetic electrons averaged over a nuclear period. This, in turn, is taken to measure the sublattice magnetization. At low temperatures (below TAE = 13 °K, where kTAE is the energy of an antiferromagnetic resonance quantum) it apperars that d log Δν / d log T decreases steadily as T decreases, where Δν = ν F(T)— νF(0). This is evidence for an energy gap in the spin wave spectrum, having its origin in the anisotropy. Detailed numerical agreement with the magnetization curve predicted by Eisele and Keffer from spin wave theory is not obtained. At higher temperatures (13.8 °K — 21.2 °K and 40 °K — 55 °K) the magnetization is substantially above that given by molecular field theoryKeywords
This publication has 5 references indexed in Scilit:
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