Year: 2005
Type: article
Abstract: We study the Ambegaokar-Eckern-Sch\"on model for a regular array of metallic grains coupled by tunnel junctions of conductance $g$ and calculate both paramagnetic and diamagnetic terms in the Kubo formula for the conductivity. We find analytically, and confirm by numerical path integral Monte Carlo methods, that for $0<g<4$ the conductivity obeys an Arrhenius law $\ensuremath{\sigma}(T)\ensuremath{\sim}\mathrm{exp}[\ensuremath{-}{E}_{\ensuremath{\sigma}}(g)∕T]$ with an effective charging energy ${E}_{\ensuremath{\sigma}}(g)$ when the temperature is sufficiently low, due to a subtle cancellation between ${T}^{2}$ inelastic-cotunneling contributions in the paramagnetic and diamagnetic terms. We present numerical results for this effective charging energy. We discuss the different ways in which the experimentally observed $\ensuremath{\sigma}(T)\ensuremath{\sim}\mathrm{exp}[\ensuremath{-}\sqrt{{T}_{0}∕T}]$ law could be attributed to disorder.
Source: Physical Review B
Authors: Y. L. Loh, V. Tripathi, M. Turlakov
Institutions: University of Cambridge, University of Oxford
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2081549926