Noise properties and ac conductance of mesoscopic diffusive conductors with screening

الأصل · EN

A theory of non-equilibrium (``shot'') noise and high frequency conductance in diffusive mesoscopic conductors with screening is presented. Detailed results are obtained for two simple geometries, for both large and short electron-electron scattering length lee, at frequencies of the order of the inverse Thouless time 1/τₜ. The conductance and the noise are found to exhibit significant frequency dependence. For L ≪ lee, the high-frequency (ωτₜ ≫ 1) shot noise spectral density Sᵢ(ω) approaches a finite value between 2eI/3 and 2eI, depending on the screening properties of the system, with temperature corrections to Sᵢ(ω) being linear in T. However, when L ≫ lee, Sᵢ(ω) grows as ω¹/⁴ (at T=0), is not upper-bound by 2eI, and has a temperature-dependent component quadratic in T. As a result, measurements of Sᵢ(ω, T) can be utilized as a probe of the strength of electron-electron scattering.