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arXiv · 1201.4913

A variational method in the problem of screening an external charge in strongly correlated metals

G. G. Guzmán-Verri·Arkady Shekhter·C. M. Varma
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Abstract

We describe a variational calculation for the problem of screening of a point charge in a layered correlated metal for dopings close to the Mott transition where the screening is non-linear due to the proximity to the incompressible insulating state. We find that external charge can induce locally incompressible regions and that the non-linear dependence of the screening on density can induce overscreening in the nearest nearby layers while preserving overall charge neutrality.

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G. G. Guzmán-Verri, Arkady Shekhter, C. M. Varma. 2013-08-30. A variational method in the problem of screening an external charge in strongly correlated metals. https://doi.org/10.1209/0295-5075%2F103%2F27003

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