Localization and Capacitance Fluctuations in Disordered Au Nano-junctions

TL;DR

This paper investigates how electronic state localization in disordered gold nano-junctions causes temperature-dependent transport phenomena, including conductance quantization at room temperature and Coulomb blockade at low temperatures, with magnetic field-induced capacitance fluctuations.

Contribution

It demonstrates that localization effects in disordered leads explain the temperature-dependent transport behaviors and capacitance fluctuations in gold nano-junctions, providing experimental validation of theoretical predictions.

Findings

Conductance quantization observed at room temperature.

Coulomb blockade effects appear at low temperature.

Capacitance fluctuates strongly with magnetic field at low temperature.

Abstract

Nano-junctions, containing atomic-scale gold contacts between strongly disordered leads, exhibit different transport properties at room temperature and at low temperature. At room temperature, the nano-junctions exhibit conductance quantization effects. At low temperatures, the contacts exhibit Coulomb-Blockade. We show that the differences between the room-temperature and low temperature properties arise from the localization of electronic states in the leads. The charging energy and capacitance of the nano-junctions exhibit strong fluctuations with applied magnetic field at low temperature, as predicted theoretically.