GAP STATES IN DILUTE MAGNETIC ALLOY SUPERCONDUCTORS

We study states in the superconducting gap induced by magnetic impurit ies using self-consistent quantum Monte Carlo with maximum entropy and formally exact analytic continuation methods. The magnetic impurity s usceptibility has different characteristics for T-0 less than or simil ar to T-c0 and T-0 greater than or similar to T-c0 (T-0: Kondo tempera ture; T-c0: superconducting transition temperature) due to the crossov er between a doublet and a singlet ground state. We systematically stu dy the location and the weight of the gap states and the gap parameter as a function of T-0/T-c0 and the concentration of the impurities.