Owing to their atomic-level perfection, carbon nanotubes exhibit unusually high electrical and thermal conductivity. Our electrical transport calculations, performed using a scattering technique based on the Landauer-Biittiker formalism, suggest that the conductance of inhomogeneous multi-wall nanotubes may show an unusual fractional quantization behavior, in agreement with recent experimental ...

The conductance of atomic-size contacts has a small, random, voltage dependent component analogous to conductance fluctuations observed in diffusive wires. A new effect is observed in gold contacts, consisting of a marked suppression of these fluctuations when the conductance of the contact is close to integer multiples of the conductance quantum. Using a model based on the Landauer-Büttiker fo...

The nature of chemical bonding and its effect on spin-polarized electron transport in Ni–C60–Ni are studied using density functional theory in conjunction with the Landauer–Büttiker formalism. The binding site on the C60 cage surface appears to have a strong influence on the electron tunneling current between Ni leads. The tunnel current has a much higher magnitude when Ni is bonded to hole sit...

We study the thermoelectric effect between a conducting lead and a Majorana edge state. In the tunneling limit, we first use the Landauer-Büttiker formalism to derive the Mott formula relating the thermopower and the differential conductance between a conducting lead and a superconductor. When the tunneling takes place between a conducting lead and a Majorana edge state, we show that a non-vani...

We have measured shot noise in single-walled carbon nanotubes with good contacts at 4.2 K at low frequencies (f=600-850 MHz). We find a strong modulation of shot noise over the Fabry-Perot pattern; in terms of the differential Fano factor the variation ranges over 0.4-1.2. The shot noise variation, in combination with differential conductance, is analyzed using two (spin-degenerate) modes with ...

We compute the thermoelectric transport parameterized by the Seebeck coefficient and thermal/electric conductance of random-alloy FeCo/MgO/FeCo(001) magnetic tunnel junctions (MTJs) from first principles using a generalized Landauer-Büttiker formalism. The thermopower is found to be typically smaller than those of Fe/MgO/Fe(001) MTJs. The (magneto-)Seebeck effect is sensitive to the details of ...

The field-emission current from realistic metal surfaces is evaluated within the density-functional theory using the Landauer-Büttiker approach. The electronic density in the surface region and the potential barrier induced by the finite electric field are calculated self-consistently using a Green’s-function embedding scheme and the full-potential linearized-augmented plane-wave method. Applic...

A local-orbital based ab initio approach to obtain the Green’s function for large heterogeneous systems is developed. First a Green’s function formalism is introduced based on exact diagonalization. Then the self energy is constructed from an incremental scheme, rendering the procedure feasible, while at the same time physical insight into different local correlation contributions is obtained. ...

We consider scattering of electrons by defects in a periodically modulated, quasi-one-dimensional structure, within a tight-binding model. Combining a transfer matrix method and a Green function method we derive a formula for a Landauer conductance and show its equivalence to the result of Kubo linear response theory. We obtain explicitly unperturbed lattice Green functions from their equations...

We show that the Landauer formula for the conductance of a nanoscale system is incomplete because it does not take into account many-body effects which cannot be treated as contributions to the single-particle transmission probabilities. We show that the physical origin of these effects is related to the viscous nature of the electron liquid and we develop a perturbative formalism, based on the...