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arXiv · 0901.3573

Origin of the 0.25-anomaly in the nonlinear conductance of a quantum point contact

S. Ihnatsenka·I. V. Zozoulenko
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Abstract

We calculate the non-linear conductance of a quantum point contact using the non-equilibrium Greens function technique within the Hartree approximation of spinless electrons. We quantitative reproduce the 0.25-anomaly in the differential conductance (i.e. the lowest plateau at 0.25-0.3*2e^2/h) as well as an upward bending of higher conductance half-integer plateaus seen in the experiments, and relate these features to the non-linear screening and pinning effects.

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S. Ihnatsenka, I. V. Zozoulenko. 2009-01-22. Origin of the 0.25-anomaly in the nonlinear conductance of a quantum point contact. https://doi.org/10.1103/physrevb.79.235313

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