Abstract:
A microscopic theory of a $SIS$ structure containing ordered magnetic impurities in the region of the potential barrier and near-critical temperatures is proposed. It is shown that for exchange fields $I\geqslant I_{\text{cr}}=V_N+O\biggl(\dfrac{v_{{\mathrm F}^2}}{V_N}\biggr)\biggl(\dfrac{v_{\mathrm F}}{V_N}\ll 1\biggr)$ the weak link between the supereonduetors is absent because of the complete destruction of the barriertunneling Cooper pairs. The behavior of the order parameter near the barrier is studied, and boundary conditions for the Ginzburg-Landan equation are established. In the region $0\leqslant I\leqslant I_{\text{cr}}$ a general expression is obtained for the Josephson current. It is noted that for $I\lesssim I_{\text{cr}}$ the critical current depends on the temperature through the factor $(T_{\mathrm c}-T)^2$.