相关论文: Excess conductance in normal-metal/superconductor …

The Heusler alloy is used as an electrode of magnetic tunneling junctions. The junctions are deposited by magnetron dc sputtering using shadow mask techniques with AlO_{x} as a barrier and cobalt as counter electrode. Measurements of the…

The order parameter of bulk two-dimensional superconductors is classified as nodal, if it vanishes for a direction in momentum space, or gapful if it does not. Each class can be topologically nontrivial if Andreev bound states are formed at…

Ramp-type junctions of $\rm Au-Bi_2Se_3-NbN$ were prepared on top of a bottom gate comprised of a $\rm SrTiO_3$ gate-insulator film on $\rm NbN$ gate-electrode layer on (100) $\rm SrTiO_3$ wafer. Two wafers with gate-insulator thickness of…

We propose a new approach of smearing origins of a zero-bias conductance peak (ZBCP) in high-Tc superconductor tunnel junctions through the analysis based on the circuit theory for a d-wave pairing symmetry. The circuit theory has been…

We propose a new type of a transition edge sensor based on an Al/AlOx/Ti/AlOx/Al superconductor - insulator - superconductor - insulator - superconductor (SIS'IS) structure. It exhibits sharp dependence of zero bias resistance on…

We show that elastic currents that take into account variations of the tunnel transmitivity with voltage and a large ratio of majority to minority spin densities of states of the $s$ band, can account for the low voltage current anomalies…

We consider an Anderson impurity (A) weakly connected to a superconducting electrode (S) on one side and a superconducting or a normal metal electrode (N) on the other side. A general path integral formalism is developed and the response of…

We investigate charge transport in two-dimensional ferromagnet/feromagnet junction on a topological insulator. The conductance across the interface depends sensitively on the directions of the magnetizations of the two ferromagnets, showing…

We develop a theory of current-voltage (I-U) characteristics for superconductor-normal metal-superconductor (SNS) junctions. At small voltages and sufficiently low temperatures the I-U characteristics of the junction is controlled by the…

Inverse magnetoresistance has been observed in magnetic tunnel junctions with pinhole nanocontacts over a broad temperature range. The tunnel magnetoresistance undergoes a change of sign at higher bias and temperature. This phenomenon is…

The spectrum of a segment of InAs nanowire, confined between two superconducting leads, was measured as function of gate voltage and superconducting phase difference using a third normal-metal tunnel probe. Sub-gap resonances for odd…

Zero bias anomalies in topological nanowires have recently captured significant attention, as they are possible signatures of Majorana modes. Yet there are many other possible origins of zero bias peaks in nanowires, for example, weak…

We consider the influence of the electron-electron interaction on the nonlinearity of the current-voltage characteristic of the tunnel junction at low bias (diffusive anomaly) in the presence of the classical magnetic field. We present the…

We have studied tunnel magnetoresistance (TMR) in junctions with 3d ferromagnetic electrodes. Previously we predicted that defects in the barrier would result in reduced effective polarization P of the impurity assisted current. This is…

Point contact junctions made from two pieces of MgB2 can be adjusted to exhibit either superconductor-insulator-superconductor (SIS) or superconductor-normal metal-superconductor (SNS) current-voltage characteristics. The SIS…

We present transport measurements in superconductor-nanowire devices with a gated constriction forming a quantum point contact. Zero-bias features in tunneling spectroscopy appear at finite magnetic fields, and oscillate in amplitude and…

A granular system slightly below the percolation threshold is a collection of finite metallic clusters, characterized by wide spectrum of sizes, resistances, and charging energies. Electrons hop from cluster to clusters via short insulating…

Individual metallic single-wall carbon nanotubes show unsual non-Ohmic transport behaviors at high bias fields. For low resistance contact samples, the differential conductance dI/dV increases with increasing bias, reaching a maximum at…

By lithographically fabricating an optimised Wheatstone bridge geometry, we have been able to make accurate measurements of the resistance of grain boundaries in Y1-xCaxBa2Cu3O7-d between the superconducting transition temperature, Tc, and…

We compute the tunneling density of states of doped multi-wall nanotubes including disorder and electron-electron interactions. A non-conventional Coulomb blockade reflecting nonperturbative Altshuler-Aronov-Lee power-law zero-bias…