Biepitaxial Josephson junctions and superconducting field effect transistors (SuFET) were fabricated in order to combine both techniques to a Josephson junction field effect transistor (JoFET). The Josephson junctions show RSJ-like behaviour. At 30 K a critical current density of J, = lo4 A/cm2 and an LRN-product of 0.1 mV were obtained. The oscillation of Shapiro steps with applied microwave f...

The physical nature of the currently observed dark energy in the universe is completely unclear, and many different theoretical models co-exist. Nevertheless, if dark energy is produced by vacuum fluctuations then there is a chance to probe some of its properties by simple laboratory tests based on Josephson junctions. These electronic devices can be used to perform ‘vacuum fluctuation spectros...

A junction between two topological superconductors containing a pair of Majorana fermions exhibits a "fractional" Josephson effect, 4π periodic in the superconductors' phase difference. An additional fractional Josephson effect, however, arises when the Majorana fermions are spatially separated by a superconducting barrier. This new term gives rise to a set of Shapiro steps which are essentiall...

A tight binding approach based on the Bogoliubov-de Gennes approach has been used to calculate the DC Josephson current for a lattice model for S-GNR-S junctions , for short junctions with respect to superconducting coherence length. We calculate the phase, length, width and chemical potential dependence at the Josephson junction and discuss the similarities and differences with regard to the t...

We present theoretical and experimental results on the effect of periodic perturbations on microwave-driven Josephson tunnel junctions close to a period-doubling bifurcation. The theory, which is quite general, describes how a periodic near-resonant perturbation changes the stability of the system. The phenomenon was investigated experimentally in small Nb-NbOx-Pb tunnel junctions and found to ...

An experiment that involves two distant mesoscopic SQUID rings is studied. The superconducting rings are irradiated with correlated photons, which are produced by a single microwave source. Classically correlated (separable) and quantum mechanically correlated (entangled) microwaves are considered, and their effect on the Josephson currents is quantified. It is shown that the currents tunnellin...

We consider numerically unquantized Josephson vortices at asymmetric grain boundaries in YBCO films. The study is focused on the effect of random variations of facets size on the values of fractional flux carried by these vortices. The grain boundaries are treated as Josephson junctions with a critical current density alternating along the junctions with a typical length-scale of order of the f...

Two mesoscopic SQUID rings which are far from each other, are considered. A source of twomode nonclassical microwaves irradiates the two rings with correlated photons. The Josephson currents are in this case quantum mechanical operators, and their expectation values with respect to the density matrix of the microwaves, yield the experimentally observed currents. Classically correlated (separabl...

We investigate the collective phase dynamics in conventional long Josephson junction (LJJ) stacks and in layered superconductors, exhibiting intrinsic LJJ behaviors. Using a theoretical model which accounts for both the magnetic induction effect and the breakdown of local charge neutrality (i.e., charging effect), we show that the collective motion of Josephson vortices, including the dispersio...