Showing 1 - 10 of 181
We investigate numerically the effect of non-linear interaction on conductance statistics in one dimensional disordered systems with δ peak potentials. It is shown that the non-linearity can either localize or delocalize the electronic states depending on its sign. For an attractive nonlinear...
Persistent link: https://www.econbiz.de/10011064337
The quantum site-percolation problem defined by a tight-binding one-electron Hamiltonian on regular simple cubic lattice with binary probability distribution of site energies P(ϵn) = pσ(ϵn) + (1 − p)σ(ϵn − ∞) is studied using the Landauer-Büttiker formalism and Green's function...
Persistent link: https://www.econbiz.de/10011059734
We report the effects of oxygen content on the transport properties of La0.7Ca0.3MnO3-δ thin films grown epitaxially on LaAlO3 (001) substrates by RF magnetron sputtering. The as-deposited thin films were annealed and treated by oxygen plasma to improve the oxygen content. We observe that the...
Persistent link: https://www.econbiz.de/10005050544
The parametric motion of one-electron energy levels of disordered systems near the Anderson localization transition is studied. We perform numerical calculations of the distributions of the first (level velocity) and the second (level curvature) derivatives with respect to a change of boundary...
Persistent link: https://www.econbiz.de/10010664892
A practical version of the polynomial canonical formalism is developed for normal mesoscopic systems consisting of N noninteracting electrons. Drastic simplification of calculations is attained by means of a proper ordering of excited states of the system. It results in that the exact canonical...
Persistent link: https://www.econbiz.de/10011061742
A unique experimental tool to deepen into the Boltzmann–Loschmidt controversy is provided by the NMR polarization echoes (PE). These appear when a local spin excitation, evolving with a many-body “diffusive” spin dynamics, is reversed. The attenuation of the PEs represents a progresive...
Persistent link: https://www.econbiz.de/10011062143
We consider a bidimensional discrete annular cavity with surface roughness (SR) threaded by a magnetic flux. In the ballistic regime and at half-filling, localized border-states show up. These border states contribute coherentely to the persistent current and the magnitude of the typical current...
Persistent link: https://www.econbiz.de/10011062247
We solve the Boltzmann transport equation in the two relaxation times approximation to analyze the kinetics of spatially inhomogeneous electron gas. The explicit form of the distribution function, obtained by means of the maximum entropy principle, together with moments method approach, are used...
Persistent link: https://www.econbiz.de/10011062317
Advancements and improvements in the Wigner function (WF) approach to quantum electron transport are reviewed. The concept of Wigner paths allows the formulation of the Monte Carlo simulation in strict analogy with the one used in semiclassical transport theory.
Persistent link: https://www.econbiz.de/10010748895
Graph-theoretical approach is used to study cluster formation in mesocsopic systems. Appearance of these clusters is due to discrete resonances which are presented in the form of a multigraph with labeled edges. This presentation allows to construct all non-isomorphic clusters in a finite...
Persistent link: https://www.econbiz.de/10010588897