Semi-classical dynamics of nano-electromechanical systems

TL;DR

This paper explores the complex dynamics of a nano-electromechanical system where a phonon mode interacts with electronic states, revealing how electronic currents influence oscillator behavior through a non-perturbative theoretical approach.

Contribution

It introduces a non-perturbative Langevin equation derived via Feynman-Vernon influence functional theory for analyzing oscillator dynamics in nano-electromechanical systems.

Findings

Electronic current induces non-trivial oscillator dynamics.

Effective potentials and friction coefficients are derived.

Different regimes of oscillator behavior are discussed for simple electronic configurations.

Abstract

We investigate the dynamics of a single phonon (oscillator) mode linearly coupled to an electronic few-level system in contact with external particle reservoirs (leads). A stationary electronic current through the system generates non-trivial dynamical behaviour of the oscillator. Using Feynman-Vernon influence functional theory, we derive a Langevin equation for the oscillator trajectory that is non-perturbative in the system-leads coupling and from which we extract effective oscillator potentials and friction coefficients. For the two simplest cases of a single and two coupled electronic levels, we discuss various regimes of the oscillator dynamics.