Related papers: \pi states in all-pnictide Josephson junctions
We study the emergent proximity effect in mesoscopic circuits that involve a conventional superconductor and an unconventional pnictide superconductor separated by a diffusive normal or ferromagnetic wire. The focus is placed on revealing…
We calculate the Josephson current in a diffusive superconductor/ferromagnet/superconductor junction, where the ferromagnetic region contains multiple layers (or domains). In particular, we study a configuration where there are two layers…
We study Josephson-like junctions formed by materials with antiferromagnetic (AF) order parameters. As an antiferromagnet, we consider a two-band material in which a spin density wave (SDW) arises. This could be Fe-based pnictides in the…
Josephson junctions with an intrinsic phase shift of pi, so-called pi Josephson junctions, can be realized by a weak link of a d-wave superconductor with an appropriate boundary geometry. A model for the pairing potential of an according…
The dc Josephson current through a long SNS junction receives contributions from both Andreev bound states localized in the normal region as well as from scattering states incoming from the superconducting leads. We show that in the limit…
We analyze the properties of flat-band superconductor junctions that behave differently from ordinary junctions containing only metals with Fermi surfaces. In particular, we show how in the tunneling limit the critical Josephson current…
We propose a trilayer $\pi$-junction that takes advantage of the unconventional $s_{x^2 y^2}=\cos k_x \cos k_y$ pairing symmetry which changes sign between electron and hole Fermi pockets in the iron pnictides. In addition, we also present…
We present a theory of SNS junctions, a normal metal sandwiched between two superconductors, along the crossover from the BCS to the BEC regime. We calculate the Josephson current as a function of the chemical potential relative to the band…
We study theoretically the shape of the current-phase relation in a Josephson junction comprising the Zeeman-split superconductors (ZSs) and a normal metal (N). We show that at low temperatures the Josephson current in the ZS/N/ZS junctions…
The Josephson transport and the electronic properties of a quantum dot characterized by a single level coupled to superconducting leads is analyzed. Different approximations are used and compared: the mean field approximation, the second…
In this work, we investigate the Josephson effect between a two-band superconductor either with the $s++$ (two energy gaps have the same sign and are fully gapped) pairing symmetry or $s\pm$ (two energy gaps have $\pi$ phase difference and…
We have observed the Josephson effect in junctions formed between single crystals of SrFe1.74Co0.26As2 and Ba0.23K0.77Fe2As2. I-V curves showed resistively-shunted junction characteristics, and the ac Josephson effect was observed under…
We investigate the temperature- and coupling-dependent transport through Kondo dot contacts with symmetric superconducting s-wave leads. For finite temperature T we use a superconducting extension of a selfconsistent auxiliary boson scheme,…
We investigate the Josephson radiation emitted by a junction made of a quantum dot coupled to two conventional superconductors. Close to resonance, the particle-hole symmetric Andreev states that form in the junction are detached from the…
We predict anomalous atomic-scale 0-pi transitions in a Josephson junction with a ferromagnetic-insulator (FI) barrier. The ground state of such junction alternates between 0- and pi-states when thickness of FI is increasing by a single…
Embedded in an ohmic environment, the Josephson current peak can transfer part of its weight to finite voltage and the junction becomes resistive. The dissipative environment can even suppress the superconducting effect of the junction via…
Josephson current for a system consisting of an Anderson impurity weakly coupled to two unconventional superconductors is studied and shown to be driven by a surface zero energy (mid-gap) bound-state. The repulsive Coulomb interaction in…
We fabricated high quality $\Nb/\Al_2\O_3/\Ni_{0.6}\Cu_{0.4}/\Nb$ superconductor-insulator-ferromagnet-superconductor Josephson tunnel junctions. Depending on the thickness of the ferromagnetic $\Ni_{0.6}\Cu_{0.4}$ layer and on the ambient…
We present a microscopic theory for the current through a tunnel Josephson junction coupled to a non-linear environment, which consists of an Andreev two-level system coupled to a harmonic oscillator. It models a recent experiment…
We consider a Josephson junction built with the two-dimensional semi-Dirac semimetal, which features a hybrid of linear and quadratic dispersion around a nodal point. We model the weak link between the two superconducting regions by a Dirac…