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arXiv · 1105.3912

Nonequilibrium phonon backaction on the current noise in atomic-sized junctions

Tomas Novotny·Federica Haupt·Wolfgang Belzig
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Abstract

We study backaction effects of phonon heating due to tunneling electrons on the current noise in atomic-sized junctions. Deriving a generalized kinetic approximation within the extended Keldysh Green's functions technique, we demonstrate the existence of a characteristic backaction contribution to the noise in case of low external phonon damping. We provide a physically intuitive interpretation of this contribution at large voltage in terms of slow fluctuations of the phonon occupation, and show that it generally gives a significant correction to the noise above the phonon emission threshold.

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Tomas Novotny, Federica Haupt, Wolfgang Belzig. 2011-05-19. Nonequilibrium phonon backaction on the current noise in atomic-sized junctions. https://doi.org/10.1103/physrevb.84.113107

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