Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Electron transport through quantum wires and point contacts   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.

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The categories of this paper are: econ
31
The categories of this paper are: ao-sci
17
The categories of this paper are: q-fin
33
The categories of this paper are: plasm-ph
16
The categories of this paper are: stat
30
The categories of this paper are: q-alg
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The categories of this paper are: adap-org
0
The categories of this paper are: hep-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: hep-th
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The categories of this paper are: hep-lat
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The categories of this paper are: supr-con
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The categories of this paper are: eess
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The categories of this paper are: nucl-ex
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The categories of this paper are: math-ph
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The categories of this paper are: nlin