Electrical low-frequency $1/f^{\gamma}$ noise due to surface diffusion of scatterers on an ultra low noise graphene platform

TL;DR

This study investigates how surface diffusion of adsorbed Ne atoms on graphene influences low-frequency $1/f^{eta}$ noise, revealing that clustering dynamics of surface defects significantly contribute to noise characteristics in ultra-low noise graphene devices.

Contribution

It demonstrates that surface diffusion and clustering of Ne atoms cause $1/f^{eta}$ noise in graphene, providing insights into defect dynamics affecting electronic noise.

Findings

$1/f^{eta}$ noise arises from surface diffusion of Ne atoms.

Clustering of Ne atoms influences the noise spectrum.

Graphene's low intrinsic noise allows detailed noise spectrum analysis.

Abstract

Low-frequency $1/f^{\gamma}$ noise is ubiquitous, even in high-end electronic devices. For qubits such noise results in decrease of their coherence times. Recently, it was found that adsorbed O$_2$ molecules provide the dominant contribution to flux noise in superconducting quantum interference devices. To clarify the basic principles of such adsorbant noise, we have investigated the formation of low-frequency noise while the mobility of surface adsorbants is varied by temperature. In our experiments, we measured low-frequency current noise in suspended monolayer graphene samples under the influence of adsorbed Ne atoms. Owing to the extremely small intrinsic noise of graphene in suspended Corbino geometry, we could resolve a combination of $1/f^{\gamma}$ and Lorentzian noise spectra induced by the presence of Ne. We find that the $1/f^{\gamma}$ noise is caused by surface diffusion of Ne atoms and by temporary formation of few-Ne-atom clusters. Our results support the idea that clustering dynamics of defects is relevant for understanding of $1/f$ noise in general metallic systems.