Imaging of one- and two-dimensional Fiske modes in Josephson tunnel junctions

B. Mayer; T. Doderer; R. P. Huebener; A. V. Ustinov

doi:10.1103/PhysRevB.44.12463

← Back to search

Imaging of one- and two-dimensional Fiske modes in Josephson tunnel junctions

B. Mayer, T. Doderer, R. P. Huebener, A. V. Ustinov

DOI 10.1103/PhysRevB.44.12463 · Physical Review B

T1

Active bibliographic source — not scientific approval

Bibliographic access preserves source history; it does not approve extracted materials or validate reported claims. Review warnings on each occurrence separately.

Abstract

We report on spatially resolved measurements of dynamic states of Josephson tunnel junctions in an external magnetic field. Using low-temperature scanning electron microscopy we imaged the beam-induced change of the maximum Fiske-step currents and the voltage change of current-biased step states. The excitation of one- and two-dimensional self-resonant cavity modes is clearly visible with a spatial resolution of about 3 μm. We used a 50×50 μm2 Nb/Al2O3/Nb tunnel junction representing a junction of intermediate size. Our experimental results agree well with a qualitative model for the signal generation based on the global change of the junction quality factor Q due to the local electron-beam irradiation. In addition, we present results of a calculation based on the perturbed sine-Gordon equation that takes into account the suppression of the critical current density in the area of the electron beam irradiation.

Source-reported materials — not catalogue approval

Formula	Reported Tc (K)	Pressure (GPa)	Type
Nb Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown