Difficulties in operator-based formulation of the bulk quadrupole moment

Seishiro Ono; Luka Trifunovic; Haruki Watanabe

doi:10.1103/physrevb.100.245133

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arXiv · 1902.07508

Difficulties in operator-based formulation of the bulk quadrupole moment

Seishiro Ono·Luka Trifunovic·Haruki Watanabe

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Abstract

Electric multipole moments are the most fundamental properties of insulating materials. However, the general formulation of bulk multipoles has been a long standing problem. The solution for the electric dipole moment was provided decades ago by King-Smith, Vanderbilt, and Resta. Recently, there have been attempts at generalizing Resta's formula to higher-order multipoles. We point out several issues in the recent proposals.

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Seishiro Ono, Luka Trifunovic, Haruki Watanabe. 2019-11-29. Difficulties in operator-based formulation of the bulk quadrupole moment. https://doi.org/10.1103/physrevb.100.245133

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