Fluctuation-induced tunneling conduction through RuO$_2$ nanowire contacts

TL;DR

This study investigates electronic conduction in RuO$_2$ nanowire contacts, demonstrating that fluctuation-induced tunneling theory accurately describes conduction behavior across a wide temperature range, validating the model for nanocontacts.

Contribution

It provides experimental validation of the fluctuation-induced tunneling model for nanocontacts between RuO$_2$ nanowires and gold electrodes over 1–300 K.

Findings

Conduction follows the FIT model across 1–300 K.

Contact resistance behavior matches theoretical predictions.

Validates FIT as a universal model for nanocontacts.

Abstract

A good understanding of the electronic conduction processes through nanocontacts is a crucial step for the implementation of functional nanoelectronic devices. We have studied the current-voltage ($I$-$V$) characteristics of nanocontacts between single metallic RuO$_2$ nanowires (NWs) and contacting Au electrodes which were pre-patterned by simple photolithography. Both the temperature behavior of contact resistance in the low-bias voltage ohmic regime and the $I$-$V$ curves in the high-bias voltage non-ohmic regime have been investigated. We found that the electronic conduction processes in the wide temperature interval 1--300 K can be well described by the fluctuation-induced tunneling (FIT) conduction theory. Taken together with our previous work (Lin {\it et al.}, Nanotechnology {\bf 19}, 365201 (2008)) where the nanocontacts were fabricated by delicate electron-beam lithography, our study demonstrates the general validity of the FIT model in characterizing electronic nanocontacts.