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Temperature Dependent Suppression of Conductance in Quantum Wires: Anomalous Activation Energy from Pinning of the Band Edge

Kenji Hirose·Ned S. Wingreen
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Abstract

For unpolarized electrons in a clean quantum wire, density functional theory reveals a thermally activated suppression of conductance. The activation temperature T_A grows slowly (roughly quadratically) with gate voltage due to pinning of the band edge at the chemical potential. Similar results were obtained experimentally by Kristensen et al. [Phys. Rev. B62, 10950 (2000)] for the temperature dependence of the anomalous conductance plateau near 0.7 (2e^2/h) in a quantum point contact.

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Kenji Hirose, Ned S. Wingreen. 2001-06-27. Temperature Dependent Suppression of Conductance in Quantum Wires: Anomalous Activation Energy from Pinning of the Band Edge. https://doi.org/10.1103/physrevb.64.073305

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