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Frequency-dependent counting statistics in interacting nanoscale conductors

C. Emary·D. Marcos·R. Aguado·T. Brandes
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Abstract

We present a formalism to calculate finite-frequency current correlations in interacting nanoscale conductors. We work within the n-resolved density matrix approach and obtain a multi-time cumulant generating function that provides the fluctuation statistics, solely from the spectral decomposition of the Liouvillian. We apply the method to the frequency-dependent third cumulant of the current through a single resonant level and through a double quantum dot. Our results, which show that deviations from Poissonian behaviour strongly depend on frequency, demonstrate the importance of finite-frequency higher-order cumulants in fully characterizing interactions.

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C. Emary, D. Marcos, R. Aguado, T. Brandes. 2008-01-23. Frequency-dependent counting statistics in interacting nanoscale conductors. https://doi.org/10.1103/physrevb.76.161404

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