We present a detailed analysis of the dependence of the critical current $I_c$ on an in-plane magnetic field $B$ of 0, $\pi$, and $0\text{−}\pi$ superconductor-insulator-ferromagnet-superconductor Josephson junctions. $I_c\left(B\right)$ of the 0 and the $\pi$ junction closely follows a Fraunhofer pattern, indicating a homogeneous critical current density $j_c\left(x\right)$. The maximum of $I_c\left(B\right)$ is slightly shifted along the field axis, pointing to a small remanent in-plane magnetization of the F-layer along the field axis. $I_c\left(B\right)$ of the $0\text{−}\pi$ junction exhibits the characteristic central minimum. $I_c$, however, has a finite value here, due to an asymmetry of $j_c$ in the 0 and the $\pi$ part. In addition, this $I_c\left(B\right)$ exhibits asymmetric maxima and bumped minima. To explain these features in detail, flux penetration being different in the 0 part and the $\pi$ part needs to be taken into account. We discuss this asymmetry in relation to the magnetic properties of the F-layer and the fabrication technique used to produce the $0\text{−}\pi$ junctions.

• Received 27 October 2009

DOI:https://doi.org/10.1103/PhysRevB.81.054522