The interplay between superconductivity and Coulomb interactions has been studied for more than 20 years now1–13. In low-dimensional systems, superconductivity degrades in the presence of Coulomb repulsion: interactions tend to suppress fluctuations of charge, thereby increasing fluctuations of phase. This can lead to the occurrence of a superconducting– insulator transition, as has been observ...

The phase difference between the banks of an edge-type planar Josephson junction crossing the narrow thin-film strip depends on wether or not vortices are present in the junction banks. For a vortex close to the junction this effect has been seen by Golod, Rydh, and Krasnov [Phys. Rev. Lett. 104, 227003 (2010)], who showed that the vortex may turn the junction into π type. It is shown here that...

Fast resonance frequency modulation of a superconducting stripline resonator is investigated. The experiments are performed using a novel device which integrates a hot electron detector (HED) into a superconducting stripline ring resonator. Frequency modulation is demonstrated by both applying dc current or voltage to the HED, and by applying optical illumination, with modulation frequencies of...

We describe recent progress in developing a superfluid helium analog of the superconducting dc-SQUID. The devices tested thus far are sensitive detectors of rotation as well as useful probes for studies of superfluidity. The key ingredients of the superfluid helium quantum interference device (SHeQUID) involve commercially available technology and modest cryogenic facilities. The superfluid sta...

Superconducting double-loop interferometers (bi-SQUIDs) have been introduced to produce magnetic flux sensors specifically designed exhibit ultra-highly linear voltage response as a function of the flux. These devices are very important for quantum sensing and signal processing signals oscillating at radio-frequencies range electromagnetic spectrum. Here, we report an Al bi-SQUIDs based on prox...

We investigated the properties of all-high-Tc edge-geometry Josephson weak links using superconducting YBa2Cu307+ (YBCO) electrodes and PrBa2Cu307-~ (PBCO) normal-metal layers. The fabrication of the weak-links involved first ionmilling the base YBCO film using a MgO mask to form the edge and then depositing PBCO and YBCO layers in situ by pulsed-laser deposition. The optimum PBCO films had res...