Tranverse relaxatin rate of Cu-NQR un YBa2Cu3O7-x and La2-xSrixCuO4

The temperature dependence of the nuclear transverse relaxation rate, 1/T 2 of CU-NQR in YBa 2 Cu 3 O 7-y and La 2−x Sr x CuO 4 is measured in the superconducting and the normal states. The anomalous enhancement of 1/T 2 at the Cu(1) and Cu(2) sites is observed at 35 K in YBa 2 Cu 3 O 7−y but is not observed in the superconducting La 2−x Sr x CuO 4