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Diffraction from Ordered States of Higher Multipoles

Y. Kuramoto·H. Kusunose·A. Kiss
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Abstract

Possible ways of identification are discussed of an electronic order of higher multipoles such as octupoles and hexadecapoles. A particularly powerful method is resonant X-ray scattering (RXS) using quadrupolar resonance processes called E2.The characteristic azimuthal angle dependence of Ce$_{0.7}$La$_{0.3}$B$_6$ is interpreted as evidence of antiferro-octupole order. For PrRu$_4$P$_{12}$, eightfold pattern against azimuthal angle is predicted if its metal-insulator transition is a consequence of a hexadecapole order. In non-resonant superlattice Bragg scattering, hexadecapole contribution may also be identified because of absence of quadrupole component.

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Y. Kuramoto, H. Kusunose, A. Kiss. 2006-03-31. Diffraction from Ordered States of Higher Multipoles. https://doi.org/10.1016/j.physb.2006.03.034

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