Conductance of quantum wires with self-consistent level broadening

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Abstract
The non-equilibrium Green function technique is applied to derive a quantum kinetic equation for transport in quantum wires. Calculations are done for short-range impurity scattering neglecting localisation effects. In linear response the expression obtained for conductance is equivalent to the Kubo-Greenwood formula. Scattering-induced level broadening is included by self-consistent solution for the retarded Green function. For typical scattering strengths, level broadening suppresses oscillations of conductance in agreement with experimental observations. Width fluctuations of only 2% remarkably reduce quantum size effects, in arrays of parallel wires. A non-zero temperature (T<10 K) is not limiting for observation of confinement effects in typical samples.