Sub-Poissonian phononic population in a nanoelectromechanical system

TL;DR

This paper investigates the phononic population in a nanoelectromechanical system coupled to a single-electron transistor, revealing regimes with sub-Poissonian phonon distributions and diverse fluctuation characteristics.

Contribution

It demonstrates the emergence of sub-Poissonian phononic states and analyzes their fluctuation properties in a realistic electron-phonon coupling scenario.

Findings

Sub-Poissonian phonon distributions occur under strong electron transport.

Electron Fano factor and phonon fluctuations can both be sub- or super-Poissonian.

Selective phonon state population is driven by electron transport out of equilibrium.

Abstract

Population of a phononic mode coupled to a single-electron transistor in the sequential tunneling regime is discussed for the experimentally realistic case of intermediate electron-phonon coupling. Features like a sub-Poissonian bosonic distribution are found in regimes where electron transport drives the oscillator strongly out of equilibrium with only few phonon states selectively populated. The electron Fano factor is compared to fluctuations in the phonon distribution, showing that all possible combinations of sub- and super-Poissonian character can be realized.