Noise and conductance in one-dimensional systems

Abstract

We derive an explicit form for the current correlation function of a Fermi gas in a finite sample at arbitrary degree of degeneracy. The expression so found enables a continuous investigation from diffusive to ballistic transport regimes to be carried out. For degenerate one-dimensional conductors under ballistic regime we find that the noise spectral density exhibits characteristic geometrical resonances and its low-frequency value has the universal formSI(0)=8e2KT/h, implying a universal conductanceG=2e2/h.