Electron transport through quantum wires and point contacts
Abstract
We have studied quantum wires using the Green's function technique and the density-functional theory, calculating the electronic structure and the conductance. All the numerics are implemented using the finite-element method with a high-order polynomial basis. For short wires, i.e. quantum point contacts, the zero-bias conductance shows, as a function of the gate voltage and at a finite temperature, a plateau at around 0.7G_0. (G_0 = 2e^2/h is the quantum conductance). The behavior, which is caused in our mean-field model by spontaneous spin polarization in the constriction, is reminiscent of the so-called 0.7-anomaly observed in experiments. In our model the temperature and the wire length affect the conductance-gate voltage curves in the same way as in the measured data.
Cite
@article{arxiv.cond-mat/0406163,
title = {Electron transport through quantum wires and point contacts},
author = {Paula Havu and Martti Puska and Risto Nieminen and Ville Havu},
journal= {arXiv preprint arXiv:cond-mat/0406163},
year = {2009}
}
Comments
8 pages