Transport and mu SR studies at p similar to 1/8 in the Bi-2212 and Y-123 phases

The so-called 1/8 effect, namely, the anomalous suppression of superconduct ivity at the hole concentration per Cu in the CuO2 plane, p, similar to 1/8 has been investigated in the partially Zn-substituted Bi-2212 and Y-123 ph ases by measuring the Hall effect and the muon spin relaxation, ( mu SR ). The Hall angle has been found to exhibit large enhancement at p similar to 1/8 in Bi2Sr2Ca1-xYx(Cu1-yZny)2 O8+delta with y = 0.025. In YBa2Cu3-2yZn2y O7-delta With y = 0.025, anomalous enhancement of the muon spin depolarizat ion has been observed atp similar to 1/8, indicating that the magnetic corr elation between Cu spins is enhanced atp similar to 1/8. These results supp ort the stripe model and the proposition that the 1/8 effect is common to a ll high-T-c cuprates with the CuO2 plane. PACS numbers: 74.25.Fy, 74.62.Dh, 74.25.Ha, 74.72.Hs, 74.72.Bk.