Static and dynamic properties of 0,π, and0−πferromagnetic Josephson tunnel junctions

Abstract

We present experimental studies of static and dynamic properties of 0, $\ensuremath{\pi}$, and $0\text{\ensuremath{-}}\ensuremath{\pi}$ superconductor-insulator-ferromagnet-superconductor (SIFS) Josephson junctions of small and intermediate length. In the underdamped limit, these junctions exhibit a rich dynamical behavior such as resonant steps on the current-voltage characteristics. Varying the experimental conditions, zero-field steps, Fiske steps, and Shapiro steps are observed with a high resolution. A strong signature of the $0\text{\ensuremath{-}}\ensuremath{\pi}$ Josephson junction is demonstrated by measuring the critical current as a function of two components (${B}_{x}$ and ${B}_{y}$) of an in-plane magnetic field. The experimental observation of a half-integer zero-field step in $0\text{\ensuremath{-}}\ensuremath{\pi}$ SIFS junctions is presented.