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arXiv · 0803.3503

Boundary-mediated electron-electron interactions in quantum point contacts

Vincent Thomas Francois Renard·O. A. Tkachenko·V. A. Tkachenko·T. Ota·N. Kumada·J. -C. Portal·Y. Hirayama
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Abstract

An unusual increase of the conductance with temperature is observed in clean quantum point contacts for conductances larger than 2e^2/h. At the same time a positive magnetoresistance arises at high temperatures. A model accounting for electron-electron interactions mediated by bound- aries (scattering on Friedel oscillations) qualitatively describes the observation. It is supported by numerical simulation at zero magnetic field.

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Vincent Thomas Francois Renard, O. A. Tkachenko, V. A. Tkachenko, T. Ota, N. Kumada, J. -C. Portal, Y. Hirayama. 2008-04-07. Boundary-mediated electron-electron interactions in quantum point contacts. https://doi.org/10.1103/physrevlett.100.186801

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