INTERLAYER COUPLING AND SUPERCONDUCTING PROPERTIES OF THE TRIPLE-LAYER COMPOUND B0.6C0.4(SR0.25BA0.75)(2)CA2CU3O9

We report the experimental results on the reversible magnetization of the triple-layer compound B0.6C0.4(Sr0.25Ba0.75)(2)Ca2Cu3O9 with T-c s imilar or equal to 119 K. In comparison with HgBa2Ca2Cu3O8+delta which is the same triple-layer compound, this superconductor showed enhance d interlayer coupling due to relatively short interlayer spacing. This feature was reflected by the three-dimensional scaling behavior of th e fluctuation-induced magnetization around T-c(H). On the other hand, the charge-carrier density calculated from the conventional theories w as significantly smaller than the value on HgBa2Ca2Cu3O8+delta. The re latively large penetration depth lambda(ab)(0) = 214 nm of this superc onductor might be due to the small carrier density. We conclude that t he competition between enhanced interlayer coupling strength and reduc ed carrier density make the T-c of B0.6C0.4(Sr0.25Ba0.75)(2)Ca2Cu3O9 l ower than that of HgBa2Ca2Cu3O8+delta.