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arXiv · 2107.04690

Three-electron bunches in occupation of a 5-site Coulomb cluster

R. E. Putnam, Jr.·M. E. Raikh
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Abstract

Attraction of like charges in a localized system implies that, upon increasing the Fermi energy, the occupation of the system changes as, n\rightarrow (n+2), while the occupation, (n+1), is skipped. In this way, the attraction translates into the bunching of electrons. For a localized system of N=4 sites, attraction of electrons manifests itself in skipping of n=2 occupation. The origin of the attraction is rearrangement of the occupations of the surrounding sites which plays the role of a polaronic effect. We consider an N=5-site cluster and demonstrate that, with screened Coulomb repulsion, three-electron bunching becomes possible, i.e. the change of occupation n=1\rightarrow n=4 with n=2 and n=3 occupations skipped.

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R. E. Putnam, Jr., M. E. Raikh. 2021-07-09. Three-electron bunches in occupation of a 5-site Coulomb cluster. https://doi.org/10.1103/physrevb.104.195425

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