SYSTEMATIC BEHAVIOR OF THE INPLANE PENETRATION DEPTH IN D-WAVE CUPRATES

We report the temperature (T) and oxygen concentration dependences of the penetration depth of grain-aligned YBa2Cu3O7-delta with delta= 0.0 , 0.3, and 0.43. The values of the in-plane lambda(ab)(0) and out-of-p lane lambda(c)(0) penetration depths, the low-temperature linear term in lambda(ab)(T), and the ratio [lambda(c)(0)/lambda(ab)(0)] were foun d to increase with increasing delta. The systematic changes of the lin ear term in lambda(ab)(T) with T-c found here and in recent work on Hg Ba2Can-1CunO2n+2+delta(n = 1 and 3) are discussed.