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arXiv · 1712.05529

Stability of ferromagnetism in many-electron systems

Tadahiro Miyao
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Abstract

We construct a model-independent framework describing stabilities of ferromagnetism in strongly correlated electron systems; Our description relies on the operator theoretic correlation inequalities. Within the new framework, we reinterpret the Marshall-Lieb-Mattis theorem and Lieb\rq{}s theorem; in addition, from the new perspective, we prove that Lieb\rq{}s theorem still holds true even if the electron-phonon and electron-photon interactions are taken into account. We also examine the Nagaoka-Thouless theorem and its stabilities. These examples verify the effectiveness of our new viewpoint.

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Tadahiro Miyao. 2017-12-15. Stability of ferromagnetism in many-electron systems. https://arxiv.org/abs/1712.05529

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