Аннотация:In this work we have demonstrated that the structures composed from longitudinally oriented normal
metal and ferromagnetic films in the weak link region can be used as reliable φ-junction (Josephson
devices with nontrivial ground state phase (0<φ<π) without external current). In this case F-layer
opens a window of parameters to the relatively small amplitude A of the first harmonics in the current-
phase relation (I(φ) = A sin(φ) + B sin(2φ)+...) and N-layer provides the negative sign of the
second one, which are required for φ-state existence. To prove it, in the frame of Usadel equations we
solved two dimensional boundary problem for different geometries of S-NF-S structures and found
analytical criteria of φ-state existence. Also we took into account the impact of proximity effect at
NF-interface. Finally we made numerical estimates and showed the structure with scale in order of
100 nm and critical current equal to 3 μA in the φ-state.
