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Effects of short-range interactions on transport through quantum point contacts: A numerical approach

Andreas Lassl·Peter Schlagheck·Klaus Richter
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Abstract

We study electronic transport through a quantum point contact, where the interaction between the electrons is approximated by a contact potential. Our numerical approach is based on the non-equilibrium Green function technique which is evaluated at Hartree-Fock level. We show that this approach allows us to reproduce relevant features of the so-called "0.7 anomaly" observed in the conductance at low temperatures, including the characteristic features in recent shot noise measurements. This is consistent with a spin-splitting interpretation of the process, and indicates that the "0.7 anomaly" should also be observable in transport experiments with ultracold fermionic atoms.

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Andreas Lassl, Peter Schlagheck, Klaus Richter. 2006-11-17. Effects of short-range interactions on transport through quantum point contacts: A numerical approach. https://doi.org/10.1103/physrevb.75.045346

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