相关论文: A classical statistical model for distributions of…
Josephson junctions and superconducting wires when probed with current pulses exhibit stochastic switching from superconducting to a stable non-zero voltage state. Electrical current dependence of the switching probability (so called…
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…
We investigate, by experiments and numerical simulations, thermal activation processes of Josephson tunnel junctions in the presence of microwave radiation. When the applied signal resonates with the Josephson plasma frequency oscillations,…
Swept bias experiments carried out on Josephson junctions yield the distributions of the probabilities of early switching from the zero voltage state. Kramers' theory of thermally activated escape from a one-dimensional potential is well…
We investigate, by experiments and numerical simulations, thermal activation processes of Josephson tunnel junctions in the presence of microwave radiation. When the applied signal resonates with the Josephson plasma frequency oscillations,…
The quantum character of Josephson junctions is ordinarily revealed through the analysis of the switching currents, i.e. the current at which a finite voltage appears: A sharp rise of the voltage signals the passage (tunnel) from a trapped…
We have investigated the classical phase dynamics of underdamped ferromagnetic Josephson junctions by measuring the switching probability in both the stationary and nonstationary regimes down to 350 mK. We found the escape temperature to be…
A quantum mechanical analysis of the Josephson phase escape in the presence of both dc and ac bias currents is presented. We find that the potential barrier for the escape of the phase is effectively suppressed as the resonant condition…
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…
We investigate the dynamics of the phase variable of an ideal underdamped Josephson junction in switching current experiments. These experiments have provided the first evidence for macroscopic quantum tunneling in large Josephson junctions…
We have studied the switching behaviour of a small capacitance Josephson junction both in experiment, and by numerical simulation of a model circuit. The switching is a comples process involving the transition between two dynamical states…
We study switching current distributions in superconducting nanostrips using theoretical models and numerical simulations. Switching current distributions are commonly measured in experiments and may provide a window into the microscopic…
We have identified anomalous behavior of the escape rate out of the zero-voltage state in Josephson junctions with a high critical current density Jc. For this study we have employed YBa2Cu3O7-x grain boundary junctions, which span a wide…
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…
We revisit the interpretation of earlier low temperature experiments on Josephson junctions under the influence of applied microwaves. It was claimed that these experiments unambiguously established a quantum phenomenology with discrete…
The evidence for macroscopic quantum tunneling (MQT) in Josephson junctions at low temperatures has been reassessed. Swept bias escape distributions have been modeled with an algorithm-based simulation and the results compared with data…
We discuss heat transport through a Josephson tunnel junction under various bias conditions. We first derive the formula for the cooling power of the junction valid for arbitrary time dependence of the Josephson phase. Combining it with the…
Switching current distributions have for decades been an indispensable diagnostic tool for studying Josephson junctions. They have played a key role in testing the conjecture of a macroscopic quantum state in junctions at millikelvin…
In this Chapter we investigate with the methods of signal detection the response of a Josephson junction to a perturbation to decide if the perturbation contains a coherent oscillation embedded in the background noise. When a Josephson…
A crossover at a temperature T* in the temperature dependence of the width s of the distribution of switching currents of moderately damped Josephson junctions has been reported in a number of recent publications, with positive ds/dT and IV…