Intrinsic Decoherence in Mesoscopic Systems

Abstract

We present measurements of the phase coherence time $τ_ϕ$ in six quasi-1D Au wires and clearly show that $τ_ϕ$ is temperature independent at low temperatures. We suggest that zero-point fluctuations of the intrinsic electromagnetic environment are responsible for the observed saturation of $τ_ϕ$. We introduce a new functional form for the temperature dependence and present the results of a calculation for the saturation value of $τ_ϕ$. This explains the observed temperature dependence of our samples as well as many 1D and 2D systems reported to date.