Systematic 63Cu NQR study of the stripe phase in La1.6-xNd0.4SrxCuO4 for 0.07 ≤ x ≤ 0.25

We demonstrate that the integrated intensity of Cu-63 nuclear quadrupole resonance (NQR) in La1.6-xNd0.4SrxCuO4 decreases dramatically below the charge-stripe ordering temperature T-charge. Comparison with neutron and x-ray scattering indicates that the wipeout fraction F(T) (i.e., the missing fraction of the integrated intensity of the NQR signal) represents the charge-stripe order parameter. The systematic study reveals hull; charge-stripe order throughout the superconducting region 0.07 less than or equal to x less than or equal to 0.25. As a function of the reduced temperature t=T/T-charge, the temperature dependence: of F(t) is sharpest for the hole concentration x similar to 1/8, indicating that x similar to 1/8 is the optimum concentration for stripe formation. [S0163-1829(99)03546-8].