2020/10/27 by Akito Daido, Atsuo Shitade, Youichi Yanase
Materials Science · Mathematics · Physics and Astronomy · #Advanced Condensed Matter Physics #Condensed matter physics #Cumulant #Dipole #Electron magnetic dipole moment #Geometry #Iron-based superconductors research #Magnetic dipole #Magnetic moment #Mathematics #Multipole expansion #Physics #Quadrupole #Quadrupole magnet #Quantum mechanics #Rare-earth and actinide compounds #Symmetry (geometry) #cond-mat.mes-hall #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.102.235149
published as Phys. Rev. B 102, 235149 (2020) · 7+8 pages, 4 figures
arxiv created 2020/10/27 · openalex publication_date 2020/12/22 · arxiv updated 2021/01/04 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
Higher-rank electric/magnetic multipole moments are attracting attention these days as candidate order parameters for exotic material phases. However, the 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.