Related papers: Andreev reflection spectroscopy in strongly paired…
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…
Directional point-contact Andreev-reflection spectroscopy measurements on the Ba$_{0.55}$K$_{0.45}$Fe$_2$As$_2$ single crystals are presented. The spectra show significant differences when measured in the $ab$ plane in comparison with those…
In a recent publication, Lee $et$ $al.$ discussed experimental observation of Klein tunneling into a proximity-induced topological superconducting state of SmB$_{6}$ through the measurement of Andreev reflection with low-bias conductance…
Direct detection of superconductivity has long been a key strength of point-contact Andreev reflection. However, its applicability to atomic-scale imaging is limited by the mechanical contact of the Andreev probe. To this end, we present a…
We study unconventional superconductivity in thin exfoliated single crystals of a promising 3D topological superconductor candidate, Nb-doped Bi$_2$Se$_3$ through Andreev reflection spectroscopy and magneto-transport. Measurements of…
Andreev reflection spectroscopy has been performed on the heavy-fermion superconductor (HFS) CeCoIn$_5$ single crystals along three different crystallographic orientations, (001), (110), and (100), using Au tips as counter-electrodes.…
We perform a point-contact Andreev reflection spectroscopic study of the topological superconducting material, Cu0.25Bi2Se3, in the ballistic regime using a normal-metal gold tip. We observe distinct point-contact spectra on the…
We report point contact measurements in high quality single crystals of Cu0.2Bi2Se3. We observe three different kinds of spectra: (1) Andreev-reflection spectra, from which we infer a superconducting gap size of 0.6mV; (2) spectra with a…
Particle transport across Josephson junctions is commonly described using a simplifying approximation (often called the Andreev approximation), which assumes that excitations are fixed at the Fermi momentum and only Andreev reflections,…
In the "ballistic" regime, the transport across a normal metal (N)/superconductor (S) point-contact is dominated by a quantum process called Andreev reflection. Andreev reflection causes an enhancement of the conductance below the…
We study tunneling spectroscopy of discrete subgap Andreev states in a superconducting system. If the tunneling coupling is weak, individual levels are resolved and the conductance $G(V)$ at small temperatures is composed of a set of…
Sub-gap conductance at a large area junction with a rough interface of a ferromagnet and a high-T$_{C}$ superconductor is superimposed by multiple peaks which is not expected from an ideal point contact Andreev reflection process. We…
We observed an enhancement of the $c$-axis differential conductance around the zero-bias in Au$/$Bi$_2$Sr$_2$CaCu$_2$O$_{8+x}$ (Bi2212) junctions near the superconducting transition temperature $T_c$. We attribute the conductance…
We calculate tunneling conductance of normal metal and superconducting topological insulator CuxBi2Se3 junctions for the possible pairing symmetries. In the presence of gapless Andreev bound states (ABSs), the tunneling conductance shows a…
Using Andreev reflection (AR) as an experimental gauge of the superconducting proximity effect (PE), we assess the topological purity of the superconductivity that is induced by the c-axis PE between an s-wave superconductor and the…
Ag/BSCCO and Fe/Ag/BSCCO planar tunnel junctions were constructed in order to study experimentally the effect of an exchange potential on the spin polarized current transported through Andreev bound states appearing at the interface with a…
Tunneling spectroscopy at surfaces of unconventional superconductors has proven an invaluable tool for obtaining information about the pairing symmetry. It is known that mid gap Andreev bound states manifest itself as a zero bias…
We have investigated Andreev-reflection processes occurring at a clean interface between a $p$-type semiconductor and a conventional superconductor. Our calculations are performed within a generalized Bogoliubov-de Gennes formalism where…
We study Andreev reflection in a ballistic one-dimensional channel coupled in parallel to a superconductor via a tunnel barrier of finite length $L$. The dependence of the low-energy Andreev reflection probability $R_A$ on $L$ reveals the…
We use point contact spectroscopy (PCS) to probe the superconducting properties of electron doped $\rm{Ba(Fe_{1-x}Co_x)_2As_2}$ ($\rm{x = 0.05, 0.055, 0.07, 0.08}$) and hole doped $\rm{Ba_{0.8}K_{0.2}Fe_2As_2}$. PCS directly probes the low…