相关论文: Surface reconstruction and energy gap of supercond…
Andreev-reflection dominated transport is demonstrated in Al/n-In0.38Ga0.62As superconductor-semiconductor junctions grown by molecular beam epitaxy on GaAs(001). High junction transparency was achieved in low-doped devices by exploiting Si…
Dynamic conductance spectra are taken from Au/CeCoIn$_5$ point contacts in the Sharvin limit along the (001) and (110) directions. Our conductance spectra, reproducibly obtained over wide ranges of temperature, constitute the cleanest data…
As progress is made on thin-film synthesis of Heusler compounds, a more complete understanding of the surface will be required to control their properties, especially as functional heterostructures are explored. Here, the surface…
Complete suppression of the native n-type Schottky barrier is demonstrated in Al/InGaAs(001) junctions grown by molecular-beam-epitaxy. This result was achieved by the insertion of Si bilayers at the metal-semiconductor interface allowing…
The reconstructions of the InP(001) surface prepared by molecular beam epitaxy have been studied with in situ reflection high-energy electron diffraction (RHEED) and scanning tunneling microscopy (STM). The growth chamber contains a highly…
We develop a new theoretical approach for modelling a wide range of semiconductor-superconductor structures with arbitrary potential barriers and a spatially-dependent superconducting order parameter. We demonstrate asymmetry in the…
We study tunneling spectroscopy between a normal metal and underdoped cuprate superconductor modeled by a phenomenological theory in which the pseudogap is a precursor to the undoped Mott insulator. In the transparent tunneling limit, the…
Physical properties of Si(111)-7x7 surface of low-doped n- and p-type Si samples is studied in the liquid helium temperature region by the scanning-tunnelling microscopy and spectroscopy. Conduction required for the study is provided by…
Using the highly inhomogeneous fields of a magnetic substrate, tunable junctions between superconducting and normal state regions were created inside a thin film superconductor. The investigation of these junctions, created in the same…
We theoretically investigate the quantum transports in a junction between a superconductor and a silicene nanoribbon, under the effect of a magnetic exchange field. We find that for a narrow nanoribbon of silicene, remarkable crossed…
Using the "break-junction" technique we prepared and studied superconductor - constriction - superconductor nanocontacts in polycrystalline samples of Fe-based superconductors CeO$_{0.88}$F$_{0.12}$FeAs (Ce-1111; $T_C^{\rm bulk} = 41 \pm 1…
Andreev reflection is investigated in layered anisotropic normal metal / superconductor (N/S) systems in the case of an energy gap \Delta in S not negligible with respect to the Fermi energy E_F, as it probably occurs with high critical…
The investigation of the electronic properties of semiconductor surfaces using scanning tunnelling spectroscopy (STS) is often hindered by non-equilibrium transport of the injected charge carriers. We propose a correction method for the…
First principles calculations of the geometric and electronic structures have been performed for two coverages (0.25 ML and 0.5 ML) of C on Ni(001) to understand the mechanism of the Ni(001) reconstruction induced by carbon adsorption. The…
We evaluate the differential conductance measured in a scanning tunneling microscopy (STM) setting at arbitrary electron transmission between an STM tip and a two-dimensional (2D) superconductor with arbitrary gap structure. Our analytical…
We theoretically demonstrate unusual features of superconducting proximity effect in gapped graphene which presents a pseudospin symmetry-broken ferromagnet with a net pseudomagnetization. We find that the presence of a band gap makes the…
We have studied the superconducting Si(111)-(root7xroot3)-In surface using a 3He-based low-temperature scanning tunneling microscope (STM). Zero-bias conductance (ZBC) images taken over a large surface area reveal that vortices are trapped…
We experimentally investigate charge transport through a single planar junction between Cd$_3$As$_2$ Dirac semimetal and a normal Au lead. For non-superconducting bulk Cd$_3$As$_2$ samples, we observe non-Ohmic $dV/dI(V)$ curves, which…
Electrons incident from a normal metal onto a superconductor are reflected back as holes - a process called Andreev reflection. In a normal metal where the Fermi energy is much larger than a typical superconducting gap, the reflected hole…
We present atomic scale images of a V_2O_3 (0001)-surface, which show that the surface is susceptible to reconstruction by dimerization of vanadium ions. The atomic order of the surface depends sensitively on the surface preparation.…