Theory of Elastic Neutron Scattering by Ordered Magnetic Octupoles inf-Electron Systems

The symmetry property and characteristic momentum dependence of elastic neutron scattering spectra due to ordered magnetic octupoles in f -electron compounds are studied theoretically. In particular, it is shown through a form factor analysis of Ce 1- x La x B 6 that a recent observation by Kuwahara et al. [J. Phys. Soc. Jpn. 76 (2007) 093702] is interpreted as a realization of such a novel scattering mechanism. A possible neutron scattering by field-induced octupoles in the quadrupolar phases is also discussed.

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