ZEITSCHRIFT FUR PHYSIK B-CONDENSED MATTER 89, 199-207 (1992)

THE TIME-DEPENDENT PROJECTION OPERATOR METHOD FOR TUNNELING IN JOSEPHSON-JUNCTIONS

H. N. Cam, E. Heiner

The time-dependent projector method of quantum statistics is applied to study the process of Josephson tunneling, being considered in a simplified microscopic model. Owing to the symmetry of the Hamiltonian, the evolution equations for dynamic variables, governing the motion in the junction, are derived exactly within the framework of different observation levels. The results show that the treatment of the Josephson junction by the projector technique illustrates the flexibility and power of this approach for an adequate description of dynamic processes in solids.