We report on superconducting(SC) characteristics for oxygen-reduced Cu-based five-layered high-temperature superconductor (Cu,C)Ba2Ca4Cu5Oy(Cu-1245(OPT)), which includes five-fold outer planes (OP) and four-fold inner planes (IP).As a result of the reduction of the carrier density, the bulk SC for Cu-1245 (OPT) takes place at the nearly optimally-doped OP with Tc= 98 K that is different from previously-reported Cu-1245(OVD) where IP plays a primary role for the onset of SC. It gives an evidence that the carrier density of the optimally-doped layer determines its bulk Tc.Static antiferromagnetic(AFM) order is evidenced at IPs by zero-field Cu-NMR at low temperature, irrespective of the SC transition at OPs below 98K. This AFM state at IPs is characterized by a carrier localization at low temperatures due to disorder effect, whereas the carrier densities in each layer are similar to Hg-1245(OPT) where the AFM metallic state are realized in IPs. This finding reinforces the phase diagram in which the AFM metallic phase exists between AFM insulator and SC states for the case of ideally-flat CuO2 plane without disorder.
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