Related papers: Optical responses of the switching currents in Al …
Current-biased Josephson junctions can act as detectors of electromagnetic radiation. At optimal conditions, their sensitivity is limited by fluctuations causing stochastic switching from the superconducting to the resistive state. This…
The effect of dc electrical stress and breakdown on Josephson and quasiparticle tunneling in Nb/Al/AlOx/Nb junctions with ultrathin AlOx barriers typical for applications in superconductor digital electronics has been investigated. The…
The escape of a small current-biased Josephson tunnel junction from the zero voltage state in the presence of weak microwave radiation is investigated experimentally at low temperatures. The measurements of the junction switching current…
In this work we give a characterization of the RF effect of memory switching on Nb-Al/AlOx-(Nb)-Pd$_{0.99}$Fe$_{0.01}$-Nb Josephson junctions as a function of magnetic field pulse amplitude and duration, alongside with an electrodynamical…
We study photon assisted tunneling in Nb/AlOx/Nb Josephson junctions. A quantitative calibration of the microwave field in the junction allowed direct verification of the quantum efficiency of microwave photon detection by the junctions. We…
Superconducting tunnel junctions are being developed for application as photon detectors in astronomy. We present the latest results on the development of very high quality, very low critical temperature junctions, fabricated out of pure Al…
We present switching current measurements in niobium-aluminum oxide-niobium underdamped Josephson rings. Underdamped Josephson rings display hysteretic current-voltage curves which can be characterized by their switching current, the value…
We have developed a technique to fabricate sub-micron, 0.6 um x 0.6 um Al-AlOx-Nb tunnel junctions using a standard e-beam resist, angle evaporation and double oxidation of the tunneling barrier, resulting in high quality niobium, as…
We show that less than 10% of the barrier area dominates the electron tunneling in state-of-art Al/AlOx/Al Josephson junctions. They have been studied by transmission electron microscopy, specifically using atomic resolution annular dark…
We report on the successful fabrication of low leakage aluminium superconducting tunnel junctions with very homogeneous and transparent insulating barriers. The junctions were tested in an adiabatic demagnetisation refrigerator with a base…
Electrical properties of Josephson junctions Nb/FeSi/Nb with superconductor/ferromagnet (S/F)interfaces are presented. Due to Andreev reflection the nearly exact quadruple enhancement of the tunnel junction differential conductance compared…
We report the demonstration of dc and ac Josephson effects as well as tunneling spectroscopy measurements on Nb/Al2O3/Al/MgB2 thin films heterostructures. Data on dc Josephson effect suggest the presence of two characteristic critical…
We investigate tunnel ferromagnetic Josephson junctions based on Superconductor-Insulator-thin superconductor-Ferromagnet-Superconductor multilayers. A comparative study of their electrodynamic properties is performed for junctions with…
Experiments on the distributions of switching currents in Josephson junctions are sensitive probes of the mechanism by which a junction changes abruptly to a finite voltage state. At low temperatures data exhibit smooth and gradual…
The most commonly used physical realization of superconducting qubits for quantum circuits is a transmon. There are a number of superconducting quantum circuits applications, where Josephson junction critical current reproducibility over a…
An application-specific Josephson generator is being developed as an on-chip calibration source for single-microwave-photon detectors operating below $T \sim $100 mK in the frequency range from 110 to 170 GHz. The targeted calibration power…
The microwave-driven dynamics of the superconducting phase difference across a Josephson junction is now widely employed in superconducting qubits and quantum circuits. With the typical energy level separation frequency of several GHz,…
We have probed the switching dynamics of the Josephson critical current of a superconducting weak link by measuring its voltage/current characteristics while applying an ac current bias in the range 1-200 MHz. The weak link between two Nb…
We propose a new type of a transition edge sensor based on an Al/AlOx/Ti/AlOx/Al superconductor - insulator - superconductor - insulator - superconductor (SIS'IS) structure. It exhibits sharp dependence of zero bias resistance on…
We study, both theoretically and experimentally, the features on the current-voltage characteristic of a highly transparent Josephson junction caused by transition of the superconducting leads to the normal state. These features appear due…