Studies on the anomalous Hall effect of Nd 2Mo 2O 7—Test of the chirality mechanism
Abstract
To understand the unusual behavior of the Hall resistivity ρH of Nd 2Mo 2O 7, there exist two interpretations: One is based on an idea that ρH is induced by the chirality ordering of the Mo-moments and another is based on an phenomenological expression found by the present authors' group that ρH is described as the summation of the contributions from the Mo- and Nd-moments. In order to examine the applicability of the mechanism of the chirality ordering, neutron scattering studies have been carried out on single crystals of Nd 2Mo 2O 7, and the obtained data have been analyzed together with various other accumulated data, that is, neutron Bragg intensities, magnetization curves and magnetic specific heats. From the magnetic parameters estimated by the analyses, the spin chirality ( χ) of Mo-moments or the fictitious magnetic flux ΦMo (∝ χ) has been calculated as a function of H and T by using the equation χ=< S1· S2× S3>, where the bracket means the statistical average. Comparing the calculated results with the observed ρH, we can conclude that the unusual behavior of ρH cannot be understood consistently by the chirality mechanism.
- Publication:
-
Journal of Magnetism and Magnetic Materials
- Pub Date:
- 2007
- DOI:
- 10.1016/j.jmmm.2006.10.598
- Bibcode:
- 2007JMMM..310E.544Y