Abstract :
[en] We present a method, based on characterizing efficiency fluctuations, to assess the performance of nanoscale thermoelectric junctions. This method accounts for effects typically arising in small junctions, namely, stochasticity in the junction's performance, quantum effects, and nonequilibrium features preventing a linear response analysis. It is based on a nonequilibrium Green's function (NEGF) approach, which we use to derive the full counting statistics (FCS) for heat and work, and which in turn allows us to calculate the statistical properties of efficiency fluctuations. We simulate the latter for a variety of simple models where our method is exact. By analyzing the discrepancies with the semiclassical prediction of a quantum master equation (QME) approach, we emphasize the quantum nature of efficiency fluctuations for realistic junction parameters. We finally propose an approximate Gaussian method to express efficiency fluctuations in terms of nonequilibrium currents and noises which are experimentally measurable in molecular junctions.
Commentary :
Cited References Count:97|CD8JQ|AMER PHYSICAL SOC|ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA|ISI Document Delivery No.:CD8JQ|Funding:M.E. is supported by the National Research Fund, Luxembourg, within the framework of Project No. FNR/A11/02. M.G. gratefully acknowledges support by the Department of Energy (Early Career Award, No. DE-SC0006422).
Journal Article
Scopus citations®
without self-citations
45