Noise in an SSET-resonator driven by an external field

TL;DR

This paper studies the noise characteristics of a superconducting single electron transistor (SSET) coupled to a driven resonator, revealing how spectral peak heights depend on oscillation amplitude and proposing a sensitive detection method.

Contribution

It generalizes the understanding of amplitude-dependent damping and temperature effects of SSETs for all resonator frequencies using a Langevin approach.

Findings

Spectral peak heights depend on resonator oscillation amplitude.

Peak heights can be used to detect small changes in drive amplitude.

Generalization of damping and temperature effects for all frequencies.

Abstract

We investigate the noise properties of a superconducting single electron transistor (SSET) coupled to an harmonically driven resonator. Using a Langevin equation approach, we calculate the frequency spectrum of the SSET charge and calculate its effect on the resonator field. We find that the heights of the peaks in the frequency spectra depend sensitively on the amplitude of the resonator oscillation and hence suggest that the heights of these peaks could act as a sensitive signal for detecting the small changes in the amplitude of the drive. The previously known results for the effective amplitude-dependent damping and temperature provided by the SSET for the case of a low frequency resonator are generalized for all resonator frequencies.