COHERENCE AND DESTRUCTION OF COHERENCE IN MESOSCOPIC RINGS

Recent investigations have shown that an important contribution to the magnetic response of an ensemble of mesoscopic normal metal rings at low temperatures is given by the coherent backscattering familiar from the theory of weak localization, here initiated by the electron-electron interaction. It is studied how this "collective" effect is weakened by the orbital effect of the magnetic field, by spin-orbit scattering, spin-flip scattering, and the Zeeman splitting. The renormalization of the interaction constant due to higher order contributions in the Cooper channel is discussed.