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Smearing of charge fluctuations in a grain by spin-flip assisted tunneling

Karyn Le Hur·Pascal Simon
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Abstract

We investigate the charge fluctuations of a grain (large dot) coupled to a lead via a small quantum dot in the Kondo regime. We show that the strong entanglement of charge and spin flips in this setup can result in a stable SU(4) Kondo fixed point, which considerably smears out the Coulomb staircase behavior already in the weak tunneling limit. This behavior is robust enough to be experimentally observable.

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Karyn Le Hur, Pascal Simon. 2003-04-03. Smearing of charge fluctuations in a grain by spin-flip assisted tunneling. https://doi.org/10.1103/physrevb.67.201308

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