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arXiv · 1802.09830

Equilibrium finite-frequency noise of an interacting mesoscopic capacitor studied in time-dependent density functional theory

Niklas Dittmann·Janine Splettstoesser·Nicole Helbig
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Abstract

We calculate the frequency-dependent equilibrium noise of a mesoscopic capacitor in time-dependent density functional theory (TDDFT). The capacitor is modeled as a single-level quantum dot with on-site Coulomb interaction and tunnel coupling to a nearby reservoir. The noise spectra are derived from linear-response conductances via the fluctuation-dissipation theorem. Thereby, we analyze the performance of a recently derived exchange-correlation potential with time-nonlocal density dependence in the finite-frequency linear-response regime. We compare our TDDFT noise spectra with real-time perturbation theory and find excellent agreement for noise frequencies below the reservoir temperature.

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Niklas Dittmann, Janine Splettstoesser, Nicole Helbig. 2018-02-27. Equilibrium finite-frequency noise of an interacting mesoscopic capacitor studied in time-dependent density functional theory. https://doi.org/10.1088/1742-6596/969/1/012145

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