相关论文: Microscopic origin of the conducting channels in m…

Atomic quantum point contacts accommodate a small number of conduction channels. Their number N and transmission coefficients {T_n} can be determined by analyzing the subgap structure due to multiple Andreev reflections in the…

We induce superconductivity by proximity effect in thin layers of gold and study the number of conduction channels which contribute to the current in one-atom contacts and atomic wires. The atomic contacts and wires are fabricated with a…

The conductance of atomic size contacts has a small, random, voltage dependent component analogous to conductance fluctuations observed in diffusive wires (UCF). A new effect is observed in gold contacts, consisting of a marked suppression…

The quantum transport properties of the ultrathin silver nanowires are investigated. For a perfect crystalline nanowire with four atoms per unit cell, three conduction channels are found, corresponding to three $s$ bands crossing the Fermi…

Electrical conductance through various nanocontacts between gold electrodes is studied by using the density functional theory, scalar-relativistic pseudopotentials, generalized gradient approximation for the exchange-correlation energy and…

Many experiments have shown that the conductance histograms of metallic atomic-sized contacts exhibit a peak structure, which is characteristic of the corresponding material. The origin of these peaks still remains as an open problem. In…

We present a systematic study of the ballistic electron conductance through sp and 3d transition metal atoms attached to copper and palladium crystalline electrodes. We employ the 'ab initio' screened Korringa-Kohn-Rostoker Green's function…

The electronic and transport properties of atomic-size contacts are analyzed theoretically using a self-consistent tight-binding model. Our results show that, for s-like metals, a sufficiently narrow contact exhibits well defined resonant…

Atomic-sized junctions of iron, created by controlled rupture, present unusually high values of conductance compared to other metals. This result is counter-intuitive since, at the nanoscale, body-centered cubic metals are expected to…

The continuing miniaturization of microelectronics raises the prospect of nanometre-scale devices with mechanical and electrical properties that are qualitatively different from those at larger dimensions. The investigation of these…

Recent experiments on atomic-scale metallic contacts have shown that the quantization of the conductance appears clearly only after the average of the experimental results. Motivated by these results we have analyzed a simplified model…

We present an experimental procedure for obtaining the conduction channels of low-dimensional conductors based on shot noise measurements. The transmission coefficient for each channel is determined numerically from the measured conductance…

Atomic-sized lead (Pb) contacts are deposited and dissolved in an electrochemical environment, and their transport properties are measured. Due to the electrochemical fabrication process, we obtain mechanically unstrained contacts and…

We present an experimental determination of the conduction channel distribution in lead nanoscale contacts with total conductances ranging from 1 to 15 G0, where G0=2e2/h. It is found that even for contacts having a cross section much…

In a mesoscopic conductor electric resistance is detected even if the device is defect-free. We engineer and study a cold-atom analog of a mesoscopic conductor. It consists of a narrow channel connecting two macroscopic reservoirs of…

Recently, different experiments on the transport through atomic-sized contacts made of ferromagnetic materials have produced contradictory results. In particular, several groups have reported the observation of half-integer conductance…

The electrical transport properties of atomic-scale conductors are reviewed, with an emphasis on the relations of this problem with studies on quantum size effects in metallic clusters. A brief introduction is given of the natural formalism…

In paper [1] (Avotina et al. Phys. Rev. B,74, 085411 (2006)) the effect of Fermi surface anisotropy to the conductance of a tunnel point contact, in the vicinity of which a single point-like defect is situated, has been investigated…

Using scanning tunneling microscopy, we reproducibly obtained electrical conductance spectra of superconductor- superconductor atomic point contacts formed on various atomic sites of the substrate. From the analysis of the subharmonic…

We investigate a normal metal -- superconductor (point) contact in the limit where the number of conducting channels in the metallic wire is reduced to few channels. As the effective Fermi energy drops below the gap energy, a conducting…