Current noise of a single-electron transistor coupled to a nano-mechanical resonator

TL;DR

This paper analyzes how coupling a nano-mechanical resonator to a single-electron transistor affects the current noise spectrum, revealing distinctive peaks and enhanced zero-frequency noise due to charge-position correlations.

Contribution

It provides a detailed calculation of the current noise spectrum in the classical regime for a coupled SET-resonator system, highlighting the impact of coupling strength, damping, and temperature.

Findings

Distinctive noise peaks at resonator frequency and its double.

Strong zero-frequency noise enhancement.

Noise spectrum depends on coupling, damping, and temperature.

Abstract

The current noise spectrum of a single-electron transistor (SET) coupled to a nano-mechanical resonator is calculated in the classical regime. Correlations between the charge on the SET island and the position of the resonator give rise to a distinctive noise spectrum which can be very different from that of the uncoupled SET. The current noise spectrum of the coupled system contains peaks at both the frequency of the resonator and double the resonator frequency, as well as a strong enhancement of the zero-frequency noise. The heights of the peaks are controlled by the strength of the coupling between the SET and the resonator, the damping of the resonator, and the temperature of the system.