Related papers: Critical and excess current through an open quantu…
Josephson currents are carried by sharp Andreev states within the superconducting energy gap. We theoretically study the electronic transport of a magnetically tunable nanoscale junction consisting of a quantum dot connected to two…
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,…
To reflect the asymptotic freedom in the thermal direction, a temperature-dependent coupling was proposed in the literature. We investigate its effect on QCD matter with and without strong magnetic fields. Compared with the fixed coupling…
Josephson junctions containing ferromagnetic layers are of considerable interest for the development of practical cryogenic memory and superconducting qubits. Such junctions exhibit a phase shift of $\pi$ for certain ranges of ferromagnetic…
We report specific heat measurements at magnetic fields up to 20 T on the recently discovered superconductor SmFeAsO$_{0.85}$F$_{0.15}$. The B-T diagram of a polycrystalline SmFeAsO$_{0.85}$F$_{0.15}$ sample with T$_c$ = 46 K was…
We measured unusual critical currents as functions of temperature in the zero field and as functions of a magnetic field perpendicular to the substrate surface at a given temperature close to the critical temperature in thin-film long…
We have investigated the microwave response of nanotube Josephson junctions at 600-900 MHz at microwave powers corresponding to currents from 0 to $2\times I_{\mathrm C}$ in the junction. Compared with theoretical modeling, the response of…
High quality epitaxial NbN/MgO/NbN Josephson junctions have been realized with MgO barriers up to a thickness of d=1 nm. The junction properties coherently scale with the size of barrier, and low critical current densities down to 3…
We theoretically investigate the critical current of a thermally-biased SIS Josephson junction formed by electrodes made by different BCS superconductors. The response of the device is analyzed as a function of the asymmetry parameter,…
For a flux qubit described by a two-level system of equations we propose a special time dependent external control field. We show that for a qubit placed in this field there exists a critical value of tunnel frequency. When the tunnel…
We have studied temperature and field dependencies of the critical current $I_{C}$ in the Nb-Fe$_{0.1}$Si$_{0.9}$-Nb Josephson junction with tunneling barrier formed by paramagnetic insulator. We demonstrate that in these junctions the…
Using a quantum detector, a superconductor-insulator-superconductor junction, we probe separately the emission and absorption noise in the quantum regime of a superconducting resonant circuit at equilibrium. At low temperature the resonant…
We study analytically an underdamped current-biased topological Josephson junction. First, we consider a simplified model at zero temperature, where the parity of the non-local fermionic state formed by Majorana bound states (MBSs)…
We have fabricated and studied a new kind of DC SQUID in which the magnitude and sign of the critical current of the individual Josephson junctions can be controlled by additional voltage probes connected to the junctions. We show that the…
We have developed a scheme for a high resolution measurement of the switching current distribution of a current biased Josephson tunnel junction using a timing technique. The measurement setup is implemented such that the digital control…
We consider theoretically and numerically magnetic field dependencies of the maximum supercurrent across Josephson tunnel junctions with spatially alternating critical current density. We find that two flux-penetration fields and…
We report on the switching current distributions in nano-hybrid Josephson junctions made of InAs semiconductor nanowires. Temperature dependence of the switching current distribution can be understood by motion of Josephson phase particle…
An experimental investigation of the critical current noise in underdamped niobium based Josephson junctions by a technique based on the switching current measurements is reported. By sweeping the junction with a current ramp we measure the…
Quantum computers could perform certain tasks which no classical computer can perform in acceptable times. Josephson junction circuits can serve as building blocks of quantum computers. We discuss and compare two designs, which employ…
We study a flux qubit, made of a superconducting loop interrupted by three Josephson junctions, which is subject to a temperature gradient. We show that the heat current induced by the temperature gradient, being sensitive to the…