2 7 M ay 1 99 8 Josephson Junctions defined by a Nano - Plough

Nano-ploughed Josephson Junctions as On-chip Radiation Sources

A new technique is presented which enables the fabrication of highly transparent Josephson junctions in combination with mesoscopic devices. We utilize a modified AFM tip to plough grooves into superconducting material, thus defining a weak link. This weak link is made within the su-perconducting split-gates, which are used to electrostatically form a conventional quantum dot and serves as a so...

co nd - m at / 9 80 53 78 28 M ay 1 99 8 Magnetic field dependence of the critical current in stacked Josephson junctions

Modulation of the critical current across layers, I c (H), of stacked Josephson junctions (SJJs) as a function of an applied magnetic field parallel to the junction planes is studied theoretically and experimentally for different junction lengths and coupling parameters. It is shown that the I c (H) patterns of long SJJs are very complicated without periodicity in H. This is due to interaction ...

Josephson Current For a Graphene Nanoribbon Using a Lattice Model

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...

5 O ct 1 99 9 A theory of π / 2 superconducting Josephson junctions

We consider theoretically a Josephson junction with a superconducting critical current density which has a random sign along the junction's surface. We show that the ground state of the junction corresponds to the phase difference equal to π 2. Such a situation can take place in superconductor-ferromagnet-superconductor junctions.

98 05 03 6 v 2 7 M ay 1 99 8 Theoretical aspects of roAp stars