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Theory of Coupled Multipole Moments Probed by X-ray Scattering in CeB$_6$

Hiroshi N. Kono·Katsunori Kubo·Yoshio Kuramoto
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Abstract

A minimal model for multipole orders in CeB$_6$ shows that degeneracy of the quadrupole order parameters and strong spin-orbit coupling lead to peculiar temperature and magnetic-field dependences of the X-ray reflection intensity at superlattice Bragg points. Furthermore, the intensity depends sensitively on the surface direction. These theoretical results explain naturally recent X-ray experiments in phases II and III of CeB$_6$. It is predicted that under weak magnetic field perpendicular to the (111) surface, the reflection intensity should change non-monotonically as a function of temperature.

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Hiroshi N. Kono, Katsunori Kubo, Yoshio Kuramoto. 2004-04-21. Theory of Coupled Multipole Moments Probed by X-ray Scattering in CeB$_6$. https://doi.org/10.1143/jpsj.73.2948

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