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arXiv · 1302.4025

Temperature Dependence of Conductance and Thermopower Anomalies of Quantum Point Contacts

O. A. Tkachenko·V. A. Tkachenko
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Abstract

It has been shown within the Landauer single-channel approach that the presence of the 0.7 anomaly in the conductance of a ballistic microcontact and the respective plateau in the thermopower implies unusual pinning of the potential barrier height $U$ at a depth of $k_BT$ below the Fermi level $E_F$. A simple way of taking into account the effect of electron-electron interaction on the profile and temperature dependence of a smooth one-dimensional potential barrier in the lower spin degeneracy subband of the microcontact has been proposed. The calculated temperature dependences of the conductance and Seebeck coefficient agree with the experimental gate-voltage dependences, including the emergence of anomalous plateaux with an increase in temperature.

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O. A. Tkachenko, V. A. Tkachenko. 2013-02-17. Temperature Dependence of Conductance and Thermopower Anomalies of Quantum Point Contacts. https://doi.org/10.1134/s0021364012230130

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