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arXiv · 0901.2475

Tunable pseudogap Kondo effect and quantum phase transitions in Aharonov-Bohm interferometers

Luis G. G. V. Dias da Silva·Nancy Sandler·Pascal Simon·Kevin Ingersent·Sergio E. Ulloa
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Abstract

We study two quantum dots embedded in the arms of an Aharonov-Bohm ring threaded by a magnetic flux. The system can be described by an effective one-impurity Anderson model with an energy- and flux-dependent density of states. For specific values of the flux, this density of states vanishes at the Fermi energy, yielding a controlled realization of the pseudogap Kondo effect. The conductance and transmission phase shifts reflect a nontrivial interplay between wave interference and interactions, providing clear signatures of quantum phase transitions between Kondo and non-Kondo ground states.

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Luis G. G. V. Dias da Silva, Nancy Sandler, Pascal Simon, Kevin Ingersent, Sergio E. Ulloa. 2009-04-27. Tunable pseudogap Kondo effect and quantum phase transitions in Aharonov-Bohm interferometers. https://doi.org/10.1103/physrevlett.102.166806

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