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arXiv · 2111.12538

A unique one-body position operator for periodic systems

Stefano Evangelisti·Faten Abu-Shoga·Celestino Angeli·Gian Luigi Bendazzoli·J. Arjan Berger
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Abstract

In this work we proof that the one-body position operator for periodic systems that we have recently proposed [Phys. Rev. B 99, 205144] is unique modulo a phase factor and an additive constant. The proof uses several general physical constraints that a periodic one-body position operator should satisfy. We show that these constraints are sufficient to uniquely define a position operator that is compatible with periodic boundary conditions.

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Stefano Evangelisti, Faten Abu-Shoga, Celestino Angeli, Gian Luigi Bendazzoli, J. Arjan Berger. 2021-11-24. A unique one-body position operator for periodic systems. https://doi.org/10.1103/physrevb.105.235201

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