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Octupole Moment as a Hidden Order Parameter in Orbitally Degenerate f-Electron Systems

Yoshio Kuramoto·Hiroaki Kusunose
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Abstract

Possibility of a novel pseudo-scalar (octupole) order is studied theoretically for orbitally degenerate systems with strong spin-orbit coupling such as Ce$_x$La$_{1-x}$B$_6$. It is discussed that coexistence of an octupole order parameter and antiferromagnetic fluctuation should lead to drastic softening of the elastic constant by a mode-mixing effect. Nonlinear coupling between dipole, quadrupole and octupole fluctuations is taken into account in terms of a Ginzburg-Landau-type functional which is derived microscopically through path integral.

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Yoshio Kuramoto, Hiroaki Kusunose. 2000-01-18. Octupole Moment as a Hidden Order Parameter in Orbitally Degenerate f-Electron Systems. https://doi.org/10.1143/jpsj.69.671

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