Noise in an ac biased junction. Non-stationary Aharonov-Bohm effect
Abstract
Description
We study excess noise in a quantum conductor in the presence of constant voltage and alternating external field. Due to a two particle interference effect caused by Fermi correlations the noise is sensitive to the phase of the time dependent transmission amplitude. We compute spectral density and show that at T=0 the noise has singular dependence on the {\rm dc} voltage $V$ and the {\rm ac} frequency $Ω$ with cusplike singularities at integer $eV/\hbarΩ$. For a metallic loop with an alternating flux the phase sensitivity leads to an oscillating dependence of the strengths of the cusps on the flux amplitude.
10 pages, RevTeX 3.0, figures by request
10 pages, RevTeX 3.0, figures by request