Metallic nonsuperconducting phase and D-wave superconductivity in Zn-substituted La1.85Sr0.15CuO4

Measurements of the resistivity, magnetoresistance, and penetration depth w ere made on films of La1.85Sr0.15CuO4, with up to 12 at. % of Zn substitute d for the Cu. The results show that the quadratic temperature dependence of the inverse square of the penetration depth, indicative of cl-wave superco nductivity, is not affected by doping. The suppression of superconductivity leads to a metallic nonsuperconducting phase, as expected for a pairing me chanism related to spin fluctuations. The metal-insulator transition occurs in the vicinity of life k(F)l approximate to 1, and appears to be disorder driven, with the carrier concentration unaffected by doping.