Quasiclassical Green's function in the BCS pairing theory

We study a generalization of the quasiclassical Green's function which allows us to include the transfer of momentum to the particles. In this approach, we may handle Galilei transformations, rotations, and gauge transformations in a systematic way. As an example, we calculate the quasiparticle flow pattern which arises during the motion of the orbital vector in the ABM phase, and discuss the meaning of the intrinsic angular momentum of the Cooper pairs. Finally, we consider charged particles in a magnetic field, and derive a Boltzmann equation for a superconductor which applies to the Hall effect in the case of moving vortices.On leave from Institut für Théorie der Kondensierten Materie, Universität Karlsruhe.