Electrical Low-Frequency 1/fγ Noise Due to Surface Diffusion of Scatterers on an Ultra-low-Noise Graphene Platform.

Masahiro Kamada,Kirsi Tappura,Marco Will,Pertti Hakonen,Antti Laitinen,Heikki Seppä,Jayanta Sarkar,Weijun Zeng

doi:10.1021/acs.nanolett.1c02325

Masahiro Kamada, Kirsi Tappura + Show 6 more

Open Access

https://doi.org/10.1021/acs.nanolett.1c02325

Copy DOI

Abstract

Low-frequency 1/f γ noise is ubiquitous, even in high-end electronic devices. Recently, it was found that adsorbed O2 molecules provide the dominant contribution to flux noise in superconducting quantum interference devices. To clarify the basic principles of such adsorbate noise, we have investigated low-frequency noise, while the mobility of surface adsorbates is varied by temperature. We measured low-frequency current noise in suspended monolayer graphene Corbino samples under the influence of adsorbed Ne atoms. Owing to the extremely small intrinsic noise of suspended graphene, we could resolve a combination of 1/f γ and Lorentzian noise induced by the presence of Ne. We find that the 1/f γ 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 metallic systems.

Highlights

Low-frequency 1/f γ noise is ubiquitous, even in high-end electronic devices
Several physical mechanisms have been suggested as the origin of the 1/f γ noise in graphene, either via fluctuations of the chemical potential or directly via mobility fluctuations.[3−8] In addition, contact noise has been found to be relevant in many cases,[2,9,10] which may result from current crowding at the contacts.[11−13]
Since the background impurity scattering is almost nonexistent for graphene electrons, even weak scatterers such as neon atoms may make a difference in the impurity scattering and thereby alter the noise substantially

Summary

Introduction

Low-frequency 1/f γ noise is ubiquitous, even in high-end electronic devices. Recently, it was found that adsorbed O2 molecules provide the dominant contribution to flux noise in superconducting quantum interference devices. Nano Letters pubs.acs.org/NanoLett ature will lead to Lorentzian noise spectra, with characteristics specific to the adsorbent species.[28] Noble gases on graphite interact quite weakly with the substrate and the adsorbed atoms remain mobile at cryogenic temperatures.

Objectives

Results

Conclusion