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Spin-dependent thermoelectric transport coefficients in near-perfect quantum wires

T. Rejec·A. Ramsak·J. H. Jefferson
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Abstract

Thermoelectric transport coefficients are determined for semiconductor quantum wires with weak thickness fluctuations. Such systems exhibit anomalies in conductance near 1/4 and 3/4 of 2e^2/h on the rising edge to the first conductance plateau, explained by singlet and triplet resonances of conducting electrons with a single weakly bound electron in the wire [T. Rejec, A. Ramsak, and J.H. Jefferson, Phys. Rev. B 62, 12985 (2000)]. We extend this work to study the Seebeck thermopower coefficient and linear thermal conductance within the framework of the Landauer-Buettiker formalism, which also exhibit anomalous structures. These features are generic and robust, surviving to temperatures of a few degrees. It is shown quantitatively how at elevated temperatures thermal conductance progressively deviates from the Wiedemann-Franz law.

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T. Rejec, A. Ramsak, J. H. Jefferson. 2002-03-29. Spin-dependent thermoelectric transport coefficients in near-perfect quantum wires. https://doi.org/10.1103/physrevb.65.235301

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