Non-monotonic resistance noise in the charge density wave pinned state in single nanoribbons of CDW conductor NbSe$_{3}$

TL;DR

This study investigates resistance noise in NbSe₃ nanoribbons, revealing non-monotonic behavior linked to phase slip events and complex fluctuation origins in the charge density wave state.

Contribution

It reports the first observation of non-monotonic resistance noise behavior in pinned CDW states at the nanoscale, supported by analysis of thermally activated phase slips.

Findings

Non-monotonic noise vs. electric field behavior observed

Thermally activated phase slips contribute to noise

Complex temperature dependence indicates non-activated fluctuation mechanisms

Abstract

Electrical transport and broadband resistance noise measurements in an ultra low frequency window (30 mHz - 8 Hz) are carried out in single nanoribbon devices of charge density wave (CDW) conductor NbSe$_{3}$. In the temperature and electric field range where the CDW is expected to be completed pinned by residual impurities, a hitherto unseen non-monotonic behavior in the noise magnitude vs. electric field is observed. This behavior can be attributed to the proliferation of thermally activated phase slip events and this idea is supported by the observation of a smeared activated behavior described by the Dutta-Horn relation. Certain features of the temperature dependence of the noise magnitude do not follow an activated behavior pointing to a complex origin of the fluctuations in a CDW system.