Shot noise variation within ensembles of gold atomic break junctions at room temperature

Abstract

Atomic-scale junctions are a powerful tool to study quantum transport, and are frequently examined through the mechanically controllable break junction technique (MCBJ). The junction-to-junction variation of atomic configurations often leads to a statistical approach, with ensemble-averaged properties providing access to the relevant physics. However, the full ensemble contains considerable additional information. We report a new analysis of shot noise over entire ensembles of junction configurations using scanning tunneling microscope (STM)-style gold break junctions at room temperature in ambient conditions, and compare this data with simulations based on molecular dynamics (MD), a sophisticated tight-binding model, and nonequilibrium Green's functions. The experimental data show a suppression in the variation of the noise near conductances dominated by fully transmitting channels, and a surprising participation of multiple channels in the nominal tunneling regime. Comparison with the simulations, which agree well with published work at low temperatures and ultrahigh vacuum (UHV) conditions, suggests that these effects likely result from surface contamination and disorder in the electrodes. We propose additional experiments that can distinguish the relative contributions of these factors.

arXiv comment21 pages, 6 figures. To appear in J. Phys: Condens. Matt., special issue on break junctions

References in corpus (27)

• Shot Noise in Mesoscopic Conductors
• Quantum properties of atomic-sized conductors
• Formation and manipulation of a metallic wire of single gold atoms
• Observation of the e/3 Fractionally Charged Laughlin Quasiparticles
• Single-Molecule Circuits with Well-Defined Molecular Conductance
• Mechanically-Controlled Binary Conductance Switching of a Single-Molecule Junction
• Observation of Quantum Interference in Molecular Charge Transport
• Formation and Evolution of Single Molecule Junctions
• Heat dissipation in atomic-scale junctions
• Onset of dissipation in ballistic atomic wires
• Quantum suppression of shot noise in atom-size metallic contacts
• Structure and conductance histogram of atomic-sized Au contacts
• Conductance fluctuations as a tool for investigating the quantum modes in atomic size metallic contacts
• Evidence for saturation of channel transmission from conductance fluctuations in atomic-size point contacts
• Theoretical analysis of the conductance histograms and structural properties of Ag, Pt and Ni nanocontacts
• Cluster-based density-functional approach to quantum transport through molecular and atomic contacts
• Quantitative Current-Voltage Characteristics in Molecular Junctions from First Principles
• Atomic size oscillations in conductance histograms for gold nanowires and the influence of work hardening
• Regular atomic narrowing of Ni, Fe and V nanowires resolved by 2D correlation analysis
• Shot noise suppression at room temperature in atomic-scale Au junctions
• Experimental determination of conduction channels in atomic scale conductors based on shot noise measurements
• Formation and properties of metal-oxygen atomic chains
• Molecular dynamics study of the thermopower of Ag, Au, and Pt nanocontacts
• Inelastic shot noise characteristics of nanoscale junctions from first principles
• Excess noise in scanning tunneling microscope-style break junctions at room temperature
• Enhanced noise at high bias in atomic-scale Au break junctions
• Scaling of 1/f noise in tunable break-junctions

Cited by in corpus (8)

• Metallic, Magnetic and Molecular Nanocontacts
• Thermal conductance of metallic atomic-size contacts: Phonon transport and Wiedemann-Franz law
• The nature of the electrical conduction in ferromagnetic atomic-size contacts: insights from shot noise measurements and theoretical simulations
• Statistical analysis of electronic and phononic transport simulations of metallic atomic contacts
• Surface states and related quantum interference in \textit{ab initio} electron transport
• Unveil the unseen: Exploit information hidden in noise
• Evolution of shot noise in suspended lithographic gold break junctions with bias and temperature
• Anomalous electronic shot noise in resonant tunneling junctions