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arXiv · 2009.01975

Proposal for methods to measure the octupole susceptibility

M. E. Sorensen·I. R. Fisher
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Abstract

Direct means of measuring the susceptibility towards an octupole order parameter are proposed via a sixth-rank tensor property. Equivalent derivatives of more conventionally measured tensor properties, including elastic stiffness, magnetic susceptibility, and elastoresistivity, are written in full, as constrained by the symmetry of the experimentally-motivated $O_h$ point group. For simplicity, we consider the specific case of $Pr^{3+}$ ions in a cubic point symmetry with a $\Gamma_3$ crystal field ground state, but the ideas are somewhat general. Experimental feasibility of measuring these various derivatives of tensor quantities is discussed.

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M. E. Sorensen, I. R. Fisher. 2020-09-04. Proposal for methods to measure the octupole susceptibility. https://doi.org/10.1103/physrevb.103.155106

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