X iv : c on d - m at / 9 50 10 14 v 1 6 J an 1 99 5 Conductance Fluctuations of Disordered Mesoscopic Devices with Many Weakly - Coupled Probes
نویسنده
چکیده
The conductance coefficients of disordered mesoscopic devices with n probes are investigated within the noninteracting electron approximation at zero temperature. The probes are eliminated from the theoretical description at the expense of introducing non-local boundary conditions at the position of the contacts. Conductors with a large number of weak contacts are analyzed in detail. The ensemble-averaged conductance coefficients are in this case given by the so-called Hauser-Feshbach formula g ab ∼ p a p b where p a is the probability for emission of an electron into lead a. The conductance energy autocor-relation function is shown to deviate significantly from the conventional Lorentzian form and to have a negative tail.
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