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Detection of topological transitions by transport through molecules and nanodevices

A. A. Aligia·K. Hallberg·B. Normand·A. P. Kampf
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Abstract

We analyze the phase transitions of an interacting electronic system weakly coupled to free-electron leads by considering its zero-bias conductance. This is expressed in terms of two effective impurity models for the cases with and without spin degeneracy. We demonstrate using the half-filled ionic Hubbard ring that the weight of the first conductance peak as a function of external flux or of the difference in gate voltages between even and odd sites allows one to identify the topological charge transition between a correlated insulator and a band insulator.

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A. A. Aligia, K. Hallberg, B. Normand, A. P. Kampf. 2004-06-16. Detection of topological transitions by transport through molecules and nanodevices. https://doi.org/10.1103/physrevlett.93.076801

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