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arXiv · 2010.13999

Thermodynamic approach to electric quadrupole moments

Akito Daido·Atsuo Shitade·Youichi Yanase
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Abstract

Higher-rank electric/magnetic multipole moments are attracting attention these days as candidate order parameters for exotic material phases. However, quantum-mechanical formulation of those multipole moments is still an ongoing issue. In this paper, we propose a thermodynamic definition of electric quadrupole moments as a measure of symmetry breaking, following previous studies of orbital magnetic dipole moments and magnetic quadrupole moments. The obtained formulas are illustrated with a model of orbital-ordered nematic phases of iron-based superconductors.

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Akito Daido, Atsuo Shitade, Youichi Yanase. 2020-10-27. Thermodynamic approach to electric quadrupole moments. https://doi.org/10.1103/physrevb.102.235149

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