International
Tables for Crystallography Volume B Reciprocal Space Edited by U. Shmueli © International Union of Crystallography 2006 |
International Tables for Crystallography (2006). Vol. B. ch. 5.3, p. 561
Section 5.3.3.4. The dynamical theory in the case of perfect collinear antiferromagnetic crystals
aLaboratoire Louis Néel du CNRS, BP 166, F-38042 Grenoble CEDEX 9, France, and bEuropean Synchrotron Radiation Facility, BP 220, F-38043 Grenoble, France |
In this case, there is no average magnetization . It is then convenient to choose the quantization axis in the direction of and . The dispersion surface degenerates into two hyperbolic surfaces corresponding to each polarization state along this direction for any orientation of the diffraction vector relative to the direction of the magnetic moments of the sublattices. These two hyperbolic dispersion surfaces have the same asymptotes. Furthermore, in the case of a purely magnetic reflection, they are identical.
The possibility of observing a precession of the neutron polarization in the presence of diffraction, in spite of the fact that there is no average magnetization, has been pointed out by Baryshevskii (1976).
References
Baryshevskii, V. G. (1976). Particle spin precession in antiferromagnets. Sov. Phys. Solid State, 18, 204–208.Google Scholar