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Suppression of Kondo-assisted co-tunneling in a spin-1 quantum dot with Spin-Orbit interaction

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 نشر من قبل Procolo Lucignano Dr.
 تاريخ النشر 2010
  مجال البحث فيزياء
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Kondo-type zero-bias anomalies have been frequently observed in quantum dots occupied by two electrons and attributed to a spin-triplet configuration that may become stable under particular circumstances. Conversely, zero-bias anomalies have been so far quite elusive when quantum dots are occupied by an even number of electrons greater than two, even though a spin-triplet configuration is more likely to be stabilized there than for two electrons. We propose as an origin of this phenomenon the spin-orbit interaction, and we show how it profoundly alters the conventional Kondo screening scenario in the simple case of a laterally confined quantum dot with four electrons.

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