Comment on ``First-principles treatments of electron transport properties for nanoscale junctions''

Energetics and conductance in jellium modelled nanowires are investigated using the local-density-functional-based shell correction method. In analogy with studies of other finite-size fermion systems, e.g., simple-metal clusters or He-3 clusters, we find that the energetics of the wire as a function of its radius (transverse reduced dimension) leads to formation of self-selecting magic wire configurations (MWC's, i.e., discrete sequence of wire radii with enhanced stability)...

Using time-dependent current-density functional theory, we derive analytically the dynamical exchange-correlation correction to the DC conductance of nanoscale junctions. The correction pertains to the conductance calculated in the zero-frequency limit of time-dependent density-functional theory within the adiabatic local-density approximation. In particular, we show that in linear response the correction depends non-linearly on the gradient of the electron density; thus, it ...

A model is presented for the quantum transport of electrons, across finite atomic wire nanojunctions between electric leads, at zero bias limit. In order to derive the appropriate transmission and reflection spectra, familiar in the Landauer-B\"{u}ttiker formalism, we develop the algebraic phase field matching theory (PFMT). In particular, we apply our model calculations to determine the electronic conductance for freely suspended monatomic linear sodium wires (MLNaW) between...

In this paper the influence of adsorbed hydrogen on the behavior of gold nanojunctions is investigated. It is found, that the hydrogen environment has a strong effect on the conductance of atomic-sized gold junctions, which is markedly reflected by the growth of an additional peak in the conductance histogram at 0.5 quantum unit, 2e^2/h. The statistical analysis of the conductance traces implies that the new peak arises due to the hydrogen-assisted distortion of atomic gold c...

We propose a mixed analytical-ab-initio method for the accurate calculation of the conductance in monovalent atomic wires. The method relies on the most general formula for ballistic transport through a monovalent wire, whose parameters can be determined from first-principles calculations. Our central result is the demonstration of the highly non-universal behavior of the conductance, which depends on the fine details of the contacts to the leads. We are therefore able to rec...

Recent experiments showed that the last, single channel conductance step in monatomic gold contacts exhibits significant fluctuations as a function of stretching. From simulations of a stretched gold nanowire linked to deformable tips, we determine the distribution of the bond lengths between atoms forming the nanocontact and analyze its influence on the electronic conductance within a simplified single channel approach. We show that the inhomogeneous distribution of bond len...

The work presents the extended theoretical model of the electrical conductance in non-magnetic and magnetic nano-size point contacts. The developed approach describes diffusive, quasi-ballistic, ballistic and quantum regimes of the spin-resolved conductance. It is based on the electron transport through metallic junction within approach of the circular constriction. The model provides unified description of the contact resistance from Maxwell diffusive through the ballistic t...

We have studied the electrical conductance of two-dimensional (2D) random percolating networks of zero-width metallic nanowires (a mixture of rings and sticks). We toke into account the nanowire resistance per unit length and the junction (nanowire/nanowire contact) resistance. Using a mean-field approximation (MFA) approach, we derived the total electrical conductance of these nanowire-based networks as a function of their geometrical and physical parameters. The MFA predict...

We have studied the electrical conductivity of nanoring-based, transparent conductive films, these being promising elements for flexible electronic devices. Both the wire resistance and the junction resistance were taken into account. We have calculated the dependency of the electrical conductivity on the number density of the rings. We have proposed a mean-field approach to estimate the dependency of the electrical conductivity on the main parameters. Comparison of direct co...

We have developed an efficient scalable kernel method for thermal transport in open systems, with which we have computed the thermal conductance of a junction between bulk silicon and silicon nanowires with diameter up to 10 nm. We have devised scaling laws for transmission and reflection spectra, which allow us to predict the thermal resistance of bulk-nanowire interfaces with larger cross sections than those achievable with atomistic simulations. Our results indicate the ch...