Fiske modes and Eck steps in long Josephson junctions: Theory and experiments

Abstract

We report on a systematic investigation of the properties of long Josephson junctions under the application of magnetic fields generating Fiske and Eck steps in the current-voltage characteristics. Numerical data and experimental results are compared with a cavity mode-based model predicting the voltage position and the amplitude of the current singularities. The comparison shows that this model can account for the shape and for the maximum current modulation of the singularities when the field penetration overcomes Meissner shielding above the value H0=2λjjc

Radiation from Flux Flow in Josephson Junction Structures

“…In the linear regime, bαlω > 1, we Figure 4 shows voltage dependencies of J and Q for several fields. The current shows well-known sharp peaks at the Fiske-resonance frequencies, and peak amplitudes oscillate with the magnetic field [32,33,34]. The conversion coefficient Q shows smooth oscillating behavior reaching maxima given by estimate (40) at the resonances.…”

“…On the other hand, the standard analysis of transport properties of finite-size JJs uses sineGordon equation and zero-derivative boundary conditions for the oscillating part of the phase at the edges [5,32,33,34]. At the JJ edges vanishing oscillating magnetic field B = ∂ϕ/∂x leads to zero Poynting vector.…”

“…Alternatively, the phase was obtained by expansion with respect to eigenmodes [32,33]. In particular, the boundary values which determine outside irradiation are given by…”

“…(24) using the perturbation theory with respect to the Josephson current [32,33] in the limit |b −ω|b ≫ 1. Taking solution as…”

Influence of surface losses and the self-pumping effect on current-voltage characteristics of a long Josephson junction

“…The dynamical and fluctuational properties of the FFO have been intensively studied both experimentally and theoretically. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] In contrast to many other types of oscillators, the FFO fluctuations are mainly caused by internal wideband sources, such as thermal and shot noise, that result in a spectral line of emission with nearly perfect Lorentzian shape. The power in the so-called "wings" decreases much slower with frequency offset from the carrier than the Gaussian shaped spectral line obtained when external noise sources are dominant.…”