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arXiv · 2009.08095

On the Sign of Fermion-Mediated Interactions

Qing-Dong Jiang
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Abstract

We develop a unified framework for understanding the sign of fermion-mediated interactions by exploiting the symmetry classification of Green's functions. In particular, we establish a theorem regarding the sign of fermion-mediated interactions in systems with chiral symmetry. The strength of the theorem is demonstrated within multiple examples with an emphasis on electron-mediated interactions in materials.

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Qing-Dong Jiang. 2020-09-17. On the Sign of Fermion-Mediated Interactions. https://doi.org/10.1103/physrevb.103.l121107

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