NONLINEAR PHASE MEMORY EFFECTS IN MESOSCOPIC RINGS WITH SUPERCONDUCTING MIRRORS

We present an experimental study of electron phase memory effects in d isordered mesoscopic rings of a normal metal (Ag) with superconducting boundaries. Magneto resistance oscillations of two periods, h/2e and h/4e, were observed. The measurement current, and the position of the superconducting ''mirrors'' with respect to the ring, had a drastic in fluence on the h/4e component, while the h/2e one was much less sensit ive to these parameters. Such behaviour is explained in terms of influ ence of the macroscopic phase of the superconductor on the microscopic phase of the normal electron. In this context we discuss the cross-ov er from the adiabatic to the non-adiabatic regime in our system.