We theorectically investigate the dc Josephson current in the junctions of ferromagnetic superconductors (FSs) with the equal spin paring symmetry, which has been suggested for the $\mathrm{Zr}{\mathrm{Zn}}_2$. The low-temperature anomaly of the Josephson current is either presented or absent, depending on the different forms of the pair potential. It is also shown that the Josephson junctions can be used as the switches by tuning the magnetization configuration of the two FS layers.

• Received 10 April 2006

DOI:https://doi.org/10.1103/PhysRevB.73.214511