Lech S. Borkowski, Physical Review B 78, 020507(R) (2008)

Phase diagram of a d-wave superconductor with Anderson impurities

We present a self-consistent solution for a model of a d-wave superconductor with finite concentration of Anderson impurities at zero temperature using the slave boson method. We show how the phase diagram depends on the strength of interaction between impurity and extended states. For fixed impurity level energy E_0 in the Kondo limit there is one superconducting-normal-state transition for all impurity concentrations n. When E_0 is close the Fermi energy there are three such transitions for impurity concentration exceeding certain minimum value n(Gamma_0 ,E_0). If hybridization Gamma_0 is fixed and the depth of the impurity level is varied, there are always two transitions for concentration above n(Gamma_0 ,E_0).

DOI: 10.1103/PhysRevB.78.02050