Related papers: Tunnelling through a semiconducting spacer: comple…
Scanning tunneling spectroscopy measurements of superconducting thin lanthanum films grown on a normal metal tungsten substrate reveal an extraordinarily large broadening of the coherence peaks. The observed broadening corresponds to very…
Superconducting heterostructures with spin-active materials have emerged as promising platforms for engineering topological superconductors featuring Majorana bound states at surfaces, edges and vortices. Here we present a method for…
We calculate the subgap current in planar superconducting tunnel junctions with thin-film diffusive leads. It is found that the subharmonic gap structure of the tunnel current scales with an effective tunneling transparency which may exceed…
A theoretical model for tunneling spectroscopy employing tight-binding band structure, d-wave gap symmetry, group velocity, and tunneling directionality can exhibit a wide range of characteristics similar to the ones found in tunneling…
We study the spin dependent tunneling of electrons through a zinc-blende semiconductor with the indirect X (or D) minimum serving as the tunneling barrier. The basic difference between tunneling through the G vs. the X barrier is the…
Spectra of the differential tunneling conductivity for ultrathin lead films grown on Si(111)7x7 single crystals with a thickness from 9 to 50 monolayers have been studied by low-temperature scanning tunneling microscopy and spectroscopy.…
The gauge usually adopted for extracting the reduced Hamiltonian of a thin spherical shell of matter in general relativity, becomes singular when dealing with two or more intersecting shells. We introduce here a more general class of gauges…
When the thickness of the layer is smaller than the electrons mean free path, the morphology affects the conductivity directly based on the layer thickness. This issue provides basis in order to estimate the thickness of the layer by…
Employing an ab initio Screened Korringa-Kohn-Rostoker (SKKR) band structure method for a metal-vacuum-metal junction, we find that the tunnel conductance is different when it is calculated across the barrier and far from it. We attribute…
A tight binding model for scanning tunneling microscopy images of a molecule adsorbed on a metal surface is described. The model is similar in spirit to that used to analyze conduction along molecular wires connecting two metal leads and…
The problem of electron tunnelling through a symmetric semiconductor barrier based on zinc-blende-structure material is studied. The $k^3$ Dresselhaus terms in the effective Hamiltonian of bulk semiconductor of the barrier are shown to…
A formally exact expression for the tunneling current, for its separation into specular and diffuse components, and for its directionality, is given for a thick tunnel junction with rough interfaces in terms of the properties of…
Theoretical treatments of tunneling in electronic devices are often based on one-dimensional (1D) approximations. Here we show that for many nanoscale devices, such as widely studied semiconductor gate-defined quantum dots, 1D…
At low temperatures, the transport through a superconducting-normal tunnel interface is due to tunneling of electrons in pairs. The probability for this process is shown to depend on the layout of the electrodes near the tunnel junction,…
We adapt the semiclassical technique, as used in the context of instanton transitions in quantum field theory, to the description of tunneling transmissions at finite energies through potential barriers by complex quantum mechanical…
This paper presents a general model for calculating the density of states and the Cooper pair potential in proximity coupled superconducting bi- and tri-layer films. The typical example of superconducting tunnel junctions is used to show…
Complex conductivity spectra of superconducting Nb are calculated from the first principles in the frequency region around the energy gap and compared to the experimental results. The row experimental data obtained on thin films can be…
The potential of a point charge in a thin semiconducting film with the thickness below the de Broglie wavelength of the free charge carriers is calculated with and without the screening.
Disordered thin films close to the superconducting-insulating phase transition (SIT) hold the key to understanding quantum phase transition in strongly correlated materials. The SIT is governed by superconducting quantum fluctuations, which…
Semiclassical approximations for tunneling processes usually involve complex trajectories or complex times. In this paper we use a previously derived approximation involving only real trajectories propagating in real time to describe the…