Josephson junctions with tunable current-phase relation

We consider 0-[pi] Josephson junctions consisting of 0 and [pi] regions of lengths L sub(0) and L sub([pi]) with critical current densities j sub(c0) and j sub(c[pi]) respectively. The dependence of the Josephson current on the phase-shift averaged along the junction is derived. We show that these systems exhibit the main features of [phi] Josephson junctions-the ground state is doubly degenerate and the current-phase relation can be tuned in situ by applying magnetic field. In the limit of short and long 0 and [pi] regions, the current phase relation is derived analytically. In the case of intermediate lengths of 0 and [pi] regions, the current-phase relation is calculated numerically.